Cant select a range of cells

Can someone tell me why the following code gives me an error. I have so much trouble with ranges, I use the syntax as it is prescribed but I am missing something. Here is the code. I will include some code lines underneath since I imagine they wont work either.

 
Sheet2.Select
Range(Cells(R1, C1), Cells(R2, C2)).Select
    
'
'Paste data to report sheet
'
    
    Worksheets("PT Monthly Report-1").Select
    Range("PTReport1Data").Select

I eventually will be turning the range statements into copy and paste instead of select. At the moment I am using select to make sure the proper cells are being selected.

I am also attaching my complete workbook as well. Thanks

Dan

What I am doing is finding two cells that I would use to select a block of cells. The rows are constants and do not change however the starting column C1 and ending column represent a starting date and a finishing date. The columns in the spreadsheet represents dates and I want to copy the columns for a certain date range (Billing Month) and then paste them into a report worksheet which gets printed and is used to create an invoice. Since I determine the block of cells based on counting the number of days in the billing period, I have to use the cell method for determining range because it allows cells to be identified by column number and row number. If this is not the case, how can I use column numbers and row numbers to specify a block of cells.

Dan