Link multiple sheets in VBA for paste macro

HI all

I have a very basic knowledge of VBA and am trying to turn my 6 hour manual entry horror into something more streamlined i have the first part of my command which is to copy data from a selected range and to paste it into a specified range
Example

Sub Macro1()
'
' Macro1 Macro
'

'
    Sheets("Sheet2").Select
    Range("B3:AK3").Select
    Selection.Copy
    Sheets("Sheet1").Select
    Dim SelRange As Range
    ActiveSheet.Paste
End Sub

Now instead of the 4th line down where i Select Sheet1 i want to select multiple sheets.
Note: These sheets are not predetermined for example i do not want sheet 1,2,3, evrytime i may want sheet 1,2,3, then second time i run the macro i want sheet 1,2,4,

Now i know you can use a pop up a tick box window to do a similar thing with selecting multiple sheets to print but cannot work out how to apply it to my use of pasting.

Any ideas and if poss an explanation of what each line is doing so i can fully understand the code.

Cheers
Mike