Here are some quick and easy instructions to follow if your goal is to create a password protected zip file. The command is the same regardless if you are zipping up a file or a folder with all contents under that folder.
Its important that you have enough space on your hard drive available for how big the folder or file is that you are trying to zip. You can right click on the folder or file and select Get Info and that will tell you how much space you need roughly. If you run out of space on your Hard Drive for the zip file you are trying to create.. while zipping the file(s) you will eventually get an error message:
zip I/O error: No space left on device
zip error: Output file write failure (write error on zip file)
Oh yes, I get this one often because I typically never check but if I did I wouldn't of wasted over an hour for a large zip file to complete.
In order to begin you must open Terminal and browse to where you would like to store the zip file.
Next you simply run: zip -er Documents_20231010.zip /Users/shadowmac/Documents/
In the above example I am zipping up my Documents folder and everything underneath it into a password protected file called Documents_20231010.zip
After you run the command you will be prompted twice for the password you would like to use to protect your file.