New Fenix 7 user here - what should I setup first?

First, this is some amazing technology! Never had a smart watch before. As a new Fenix 7x Pro Saphire Solar user, only using a Fitbit years ago, what do I need to setup first? For context, my training is focused on Zwift and some weightlifting to maintain a bit of muscle mass. I also walk the dog a bit. I'd like to focus on dropping about 10lbs, and improving my FTP and VO2 max if possible. Being almost 50, it gets a bit more challenging, but I've been doing a lot of Zone 2 training and not enough intervals, so I think it's possible for sure. What are your favorite features of the Fenix 7 Pro? Any tips for a new user? Thanks!