Nested Do While Loop Statements with Active Cell Properties on 2 open spreadsheets

Good morning,
My manager has tasked me with building a reporting automation piece for our biggest client. Every month, they want to have an updated units and volume count for the various loan programs they offer. 1 report will be run out of our originations system and the values from that report will need to be placed on a year to date master report that contains columns for every month and a running total. I've already built this master report template, but I'm running into difficulties setting up the code that will read the monthly originations report. It appears that I will need to use nested loop statements to make this work, and since I've only used single loop statements, I suspect my syntax is off. The code is below for just one loan program. Once I figure out the correct syntax, I can replicate for all loan programs involved. The Tname spreadsheet is the originations report and ThisWorkbook is template that the data needs to be copied into. I'm trying to use active cell properties on each spreadsheet and perhaps that won't work? I'm not sure. Any assistance will be appreciated!

Sub PopulateSingleMonthData()


ThisWorkbook.Activate
fund = Range("FundedReportFilePath")
copyaddress = fund

Workbooks.Open Filename:=(copyaddress)
Tname = ActiveWorkbook.Name

Windows(Tname).Activate
Sheets("Table").Select
Range("C2").Activate

ThisWorkbook.Activate
Sheets("Report").Activate
Range("B14").Activate

Windows(Tname).Activate
    Do Until ActiveCell = "" And ActiveCell.Offset(1, 0) = ""
        If ActiveCell.Offset(-1, 0).Value = "10 YEAR FIXED SUMMARY" Then
            Do Until ActiveCell = "" And ActiveCell.Offset(1, 0) = ""
                If ActiveCell.Offset(-3, 0).Value = "10 Year - Fixed" Then
                    Windows(Tname).ActivateCell = ThisWorkbook.ActivateCell
                    ActiveCell.Offset(1, 0).Activate
                Else
                    ActiveCell.Offset(1, 0).Activate
                End If
            Loop
        Else
            Offset(-1, 0).Activate
        End If
    Loop
            

End Sub