How to convert .exe files to zip?

I need to upload a small app from floppy to my web page (Homestead Professional) but it does not support .exe files (it’s a downloadable, self-extracting zip file). I’ve been told to change the file extension to .zip (or any others) and then advise to change the extension back to .exe when downloaded. But I cannot find out how to change the .exe so Homestead will accept the upload. Help? Thanks… Dan