At my workplace, we make a new file/invoice for every customer, then we extract the information from that file to a general one where all of the clients are located.
Each cell from this general file extracts information from the created files. The used formula is this one =IF('C:\Users\VLAD\Desktop\facturas\[ra3.xlsx]Foaie1'!$E$8="","",'C:\Users\VLAD\Desktop\facturas\[ra3.xlsx]Foaie1'!$E$8)

The ''if'' formula is to leave the cell blank if nothing was to be taken from the file.

So, there's around 40 cells with this exact formula that extract information from the file, the quickest way I've found of updating them is by using the replace tool. In this case the name of the file is ra3, so I'd use replace on all 40 cells and change it for ra4, so it takes all the same information from the next invoice.

I've been wondering whether there's a quick way of doing this though, I'd ideally want to do it very quickly, since replacing one by one may take a bit longer. I'd need a macro that updates specifically the name of the file and adds +1. (f.e. next formula should automatically get updated to =IF('C:\Users\VLAD\Desktop\facturas\[ra4.xlsx]Foaie1'!$E$8="","",'C:\Users\VLAD\Desktop\facturas\[ra4.xlsx]Foaie1'!$E$8) and the next one to =IF('C:\Users\VLAD\Desktop\facturas\[ra5.xlsx]Foaie1'!$E$8="","",'C:\Users\VLAD\Desktop\facturas\[ra5.xlsx]Foaie1'!$E$8)

And so on,
I've also been wondering whether its possible to create like 100 of them in advance so they update themselves as we create the invoices, but every time I input the name of a file that does not exist excel pops up a window to look for that file.

I hope I've explained myself clearly enough, and hope you guys can help me find a solution!
As a side note, I know almost nothing about macros.