This might seem a silly question, but I come from iOS development which is a bit more restricted as we (all) know.
My question is partially answered here: Is the mac app store required?
But I still have a doubt. Basically what I want is to develop a simple app with some 3rd party frameworks in and then give it to a friend for normal usage.
Are there any restrictions in any regard? I have a free iOS and Mac developer account.
Yes, you can do that. You do not need a Mac developer account at all. I would still suggest that you code-sign the app bundle though.
The only caveat is the user would needs to change a setting on their Mac to allow it through Gatekeeper.