Copy range downwards till certain cell

In this example, you can select both your input and output range. Try this:

Sub main()

    Dim rngInput As Range, rngOutput As Range
    Dim lRow As Long, lRowEnd As Long

CalculateInput:
    Set rngInput = Application.InputBox("Select input cells", Type:=8)
    If rngInput.Columns.Count > 1 Then MsgBox "Only select cells from one column": GoTo CalculateInput
    
CalculateOutput:
    Set rngOutput = Application.InputBox("Select output cells", Type:=8)
    If rngOutput.Columns.Count > 1 Then MsgBox "Only select cells from one column": GoTo CalculateOutput
    
    With ThisWorkbook.Sheets(rngOutput.Parent.Name)
        lRow = rngOutput.Cells(1).Row
        lRowEnd = rngOutput.Rows.Count + lRow - 1
        Do
            .Cells(lRow, rngOutput.Cells(1).Column).Resize(rngInput.Rows.Count, 1) = rngInput.Value
            lRow = lRow + rngInput.Rows.Count
        Loop While lRow <= lRowEnd
        Application.Intersect(.Columns(rngOutput.Cells(1).Column), .Rows((lRowEnd + 1) & ":" & Rows.Count)).ClearContents
        .Activate
    End With
    
    Set rngInput = Nothing: Set rngOutput = Nothing
    
End Sub

Happy holidays!