if I can't find my 2023 1120S how do I fill out the Electronic Filing Information form? I am a very small one man business witth gross receipts under $200,000.

Did you use the Turbo Tax Business program?   Then the only copy is on the computer you used.   You should have saved the return as a pdf file.   Both the pdf file and data file ending in .tax2023 should be in your Documents folder then in a Turbo Tax subfolder.  If you don’t have the pdf file you need the program installed to open the .tax2023 file.   You can probably get a copy from the IRS.