Given your situation with being a first time boat owner and never having fished a tournament before, I'd also suggest fishing the first year as a co-angler. There are things you need to learn about running your boat and being in control of it before you jump onto the tournament scene as a boater. Things like learning how it handles and responds in adverse conditions, boat wakes, even just boat control while fishing. You can practice all of that while you prefish for the tourneys. The other thing I would suggest as well, is maybe when a different club has a tournament, go out and start fishing the same lake they do and fish until weigh in. Keep your best 5 in the livewell, and either ask to weigh them after the tourney, or use your own scale and compare how you did against the other boaters. This will allow you to see how you hang with the boaters and let you gauge if you want to make that jump to being a boater without having to drop some coin and potentially get your rear end handed to you to find out.
Lastly, when it comes to the actual tournament, it's important to remember that you aren't competing against other anglers, you're competing against the fish. So many people have a tendency to constantly be thinking how other anglers are doing, or see one catch a fish and second guess if you're making the right decision. You can't get caught up in that game as it never ends well, just have confidence that you're making the right decision for yourself, and at the end of the day you'll find out if you unlocked the bass's secrets better than others did. If you didn't use it as a learning experience and figure out where you went wrong, along the way.