I made my Xcode project into a .zip file. Can I send it via email as an attachment? Would it work that the person I send the project to, can unzip my file and see my entire Xcode project?
Yes. That will work.
If it's too big to email, use a cloud service (Dropbox, Google Drive, etc.) and email them the link.
Even if it's not too big for an attachment, you might consider sending them a link so they can download at their convenience, rather than having you 'push' the file into their inbox.