If you can't find a friend to teach you, I think you should consider reading a beginners book or two before anything. Well before you even get to sailing, you'll basically need to be able to operate your Macgregor 22 as a motorboat. Is your battery charged so that you can you start the engine? Do you have fuel? Can you shift it into neutral, reverse? Can you control the throttle so you can increase or decrease speed? There are no breaks on a boat (!), so you'll need to have a good understanding of how you thrust the engine in reverse to slow the boat so you don't smash into your rented dock space. Sailing books like Sailing for Dummies
should also discuss how to leave the dock and return.
You should consider bringing an anchor and anchor line with you in case you have problems returning to the dock....at least you'll be able to park the boat and won't have to panic. Definitely bring a VHF or at least a cell phone.