Importing data from a file into a tool saved in the same folder as the file

I am creating a tool to convert data from a third party vendor report into a usable layout to import into internal software. In similar tools that I've created we have simply opened the vendor report, copied the sheet, and pasted into the tool then run a macro to complete the formatting. I would like to cut out the copy/paste step and instead auto load the info from the vendor report onto the applicable tab in the tool. Any thoughts?

Additional information that may be useful:
-A copy of the tool will always be saved in the same folder as the vendor report.
-The base name of the vendor report is always the same, but it also starts with a variable client number and ends with a date. Example: 12345_Vendor Report_12.31.2025. I need the tool to know that it should load that specific file.
-The vendor report may be in csv or xlsx format. If that makes a difference I can instruct that the report be saved in whatever format makes things easier.
-My previous tools have been made by simply recording a macro. I do not have any experience in manually doing any VBA work, but I'm willing to give it a try.

Thanks!