Can someone help speed up my code?

I have a spreadsheet with travel information and I wrote code to loop through and find the specific columns I am looking for and then analyze them based on the criteria provided. I am relatively new to VBA and I am assuming there is a faster way to do this. Currently it takes about 69 seconds to execute. I dont want to use specific columns in case someone deletes a column that isnt needed. Any suggestions? Thanks

 Sub CreateSheetsWithNames()
sheets("master").Cells.EntireColumn.Hidden = False

    Dim firstrow As Range
    Dim rcell As Range
Dim rcell2 As Range
Dim rcell3 As Range
Dim rcell4 As Range
Dim rcell5 As Range
  Dim rcell6 As Range
 Dim rcell7 As Range
Dim rcell8 As Range
Dim rcell9 As Range
Dim rcell10 As Range                    
                   
    Dim bcell As Range
 Dim bcell2 As Range
Dim bcell3 As Range
Dim bcell4 As Range
Dim bcell5 As Range
Dim bcell6 As Range
Dim Bcell7 As Range
 Dim Bcell8 As Range
  Dim Bcell9 As Range
 Dim Bcell10 As Range                         
 Dim myrange As Long
Dim myrange2 As Long
Dim myrange3 As String
 Dim myrange4 As String
    Dim strnsearch As String
        Dim strnsearch2 As String
            Dim strnsearch3 As String
                Dim strnsearch4 As String
Dim strnsearch5 As String
  Dim strnsearch6 As String
   Dim strnsearch7 As String
Dim strnsearch8 As String
Dim strnsearch9 As String
 Dim strnsearch10 As String
 
    Dim ws As Worksheet
    Dim cvalue As String 
    Dim LastRow As Long
        Dim lastcolumn1 As Long
    Dim y As Long
    With sheets("master")
 
If .Range("b1") = "" Then
    lastcolumn1 = .Range("b1").End(xlDown).End(xlToRight).Column
        Else      
lastcolumn1 = .Range("b1").End(xlToRight).Column
    End If

If .Range(Cells(1, lastcolumn1).Address) = "" Then
    Set firstrow = .Range(Cells(1, lastcolumn1).Address).End(xlDown).Offset(0, 1)
            Else:  Set firstrow = .Range(Cells(1, lastcolumn1).Offset(0, 1).Address)
                End If
                
For y = firstrow.Row To .Range("A100000").End(xlUp).Row
 
strnsearch = "Document Type"
 Set bcell = .Rows().Find(What:=strnsearch, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)
   If Not bcell Is Nothing Then
    bcellletter = Col_Letter(bcell.Column)
         Else
            MsgBox ("Please designate column 'Document Type'")
                End
                    End If
                                                
strnsearch2 = "Expenses by LOA"
    Set bcell2 = .Rows().Find(What:=strnsearch2, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)
If Not bcell2 Is Nothing Then
   bcellletter2 = Col_Letter(bcell2.Column)
        Else
            MsgBox ("Please designate column 'Expenses by LOA'")
                 End
                    End If

strnsearch3 = "Document Create Date"
    Set bcell3 = .Rows().Find(What:=strnsearch3, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)

If Not bcell3 Is Nothing Then
    bcellletter3 = Col_Letter(bcell3.Column)
         Else
            MsgBox ("Please designate column 'Document Create Date'")
             End
                    End If

strnsearch4 = "Departure Date"
    Set bcell4 = .Rows().Find(What:=strnsearch4, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)
If Not bcell4 Is Nothing Then
    bcellletter4 = Col_Letter(bcell4.Column)
        Else
            MsgBox ("Please designate column 'Departure Date'")
                 End
                    End If
                    
strnsearch5 = "Last AO Approved Date"
    Set bcell5 = .Rows().Find(What:=strnsearch5, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)
 If Not bcell5 Is Nothing Then
    bcellletter5 = Col_Letter(bcell5.Column)
 Else
 MsgBox ("Please designate column 'Last AO Approved Date'")
 End
End If
                                  
strnsearch6 = "Total Trip Expenses"
    Set bcell6 = .Rows().Find(What:=strnsearch6, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)
             
If Not bcell6 Is Nothing Then
   bcellletter6 = Col_Letter(bcell6.Column)
 Else
MsgBox ("Please designate column 'Total Trip Expenses'")
End
 End If
                                                       
strnsearch7 = "TANum"
    Set Bcell7 = .Rows().Find(What:=strnsearch7, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)
            
If Not Bcell7 Is Nothing Then
    bcellletter7 = Col_Letter(Bcell7.Column)
Else
 MsgBox ("Please designate column 'TANum'")
 End
End If
                                                      
strnsearch8 = "Total Reimbursable Expenses"
    Set Bcell8 = .Rows().Find(What:=strnsearch8, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)
            
If Not Bcell8 Is Nothing Then
    bcellletter8 = Col_Letter(Bcell8.Column)
        Else
 MsgBox ("Please designate column 'Total Reimbursable Expenses'")
 End
End If
                                             
strnsearch9 = "Return Date"
    Set Bcell9 = .Rows().Find(What:=strnsearch9, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)

If Not Bcell9 Is Nothing Then
    bcellletter9 = Col_Letter(Bcell9.Column)
        Else
 MsgBox ("Please designate column 'Return Date'")
End
End If

strnsearch10 = "Current Status"
    Set Bcell10 = .Rows().Find(What:=strnsearch10, LookIn:=xlValues, _
            LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)
                                                            
If Not Bcell10 Is Nothing Then
    bcellletter10 = Col_Letter(Bcell10.Column)
        Else
            MsgBox ("Please designate column 'Current Status'")
                 End
                    End If
                                      
LastLetter = Col_Letter(lastcolumn1)
clearletter = Col_Letter(firstrow.Column)

firstrow.Value = "AUTHORIZATIONS"
firstrow.Offset(0, 1).Value = "VOUCHERS"
firstrow.Offset(0, 2).Value = "LOCAL VOUCHERS"
firstrow.Offset(0, 3).Value = "Doc create date after departure date"
firstrow.Offset(0, 4).Value = "Travel Notice Given"
firstrow.Offset(0, 5).Value = "Voucher Create date over 5 days from Return"
firstrow.Offset(0, 6).Value = "Last AO approved Date before  Doc Create Date"
firstrow.Offset(0, 7).Value = "Is Cancelled Trip Zero'd Out?"
firstrow.Offset(0, 8).Value = "Unliquidated Amount"
firstrow.Offset(0, 9).Value = "Unliquidated %"
Range(firstrow, firstrow.Offset(0, 9)).Font.Bold = True
 
For Each rcell In .Range(bcellletter & y)
For Each rcell2 In .Range(bcellletter2 & y)
For Each rcell3 In .Range(bcellletter3 & y)
For Each rcell4 In .Range(bcellletter4 & y)
For Each rcell5 In .Range(bcellletter5 & y)
For Each rcell6 In .Range(bcellletter6 & y)
For Each rcell7 In .Range(bcellletter7 & y)
For Each rcell8 In .Range(bcellletter8 & y)
For Each rcell9 In .Range(bcellletter9 & y)
For Each rcell10 In .Range(bcellletter10 & y)

If rcell.Value = "AUTH" Then
    .Range(LastLetter & y).Offset(0, 1).Value = .Range(bcellletter2 & y).Value
        End If
If rcell.Value = "VCH" Then
    .Range(LastLetter & y).Offset(0, 2).Value = .Range(bcellletter2 & y).Value
        End If
If rcell.Value = "LVCH" Then
    .Range(LastLetter & y).Offset(0, 3).Value = .Range(bcellletter2 & y).Value
        End If
        
If rcell.Value = "AUTH" And rcell4.Value < rcell3.Value Then
    .Range(LastLetter & y).Offset(0, 4).Value = "Error"
        End If

If rcell.Value = "AUTH" Then
    If rcell5.Value < rcell3.Value And rcell6.Value > 0 And rcell10.Value = "CANCELLED" Then
        .Range(LastLetter & y).Offset(0, 7).Value = "Error"
            End If
                End If
                         
If rcell.Value = "VCH" Or rcell.Value = "LVCH" Then
    If rcell3.Value - rcell9.Value > 5 Then
        .Range(LastLetter & y).Offset(0, 6).Value = "Error"
            End If
                End If
'                         
If rcell7.Value = " " Or rcell7.Value = "" And rcell2.Value > 0 Then
    .Range(LastLetter & y).Offset(0, 8).Value = .Range(bcellletter2 & y)
        .Range(LastLetter & y).Offset(0, 8).NumberFormat = "$#,##0.00"
            End If
                    
If rcell.Value = "AUTH" Then
    .Range(LastLetter & y).Offset(0, 5).Value = rcell4.Value - rcell3.Value
        .Range(LastLetter & y).Offset(0, 5).HorizontalAlignment = xlCenter
            End If
             
Next
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End With
end sub