I'm brand new to itch.io and I cannot for the life of me get this thing to work? I pressed enter as mentioned in the keyboard shortcut thing, but i just can't generate a city. the generator is added to my collection but I'm not sure how to work it whatsoever

You need to click the generator first to allow it to capture keystrokes. Or you can use the context menu (right click anywhere on the generator). Please let me know if it doesn't work for you.