First suggestion...find a shotshell reloading manual. I know Lyman publishes a good one and I bet there are a bunch of others available on the internet. Get one and study up on it. It will recommend that you follow the recipes suggested without change. The loads they publish will be safe...the loads suggestions you get on facebook, etc.,...maybe, maybe not.
I don't know if TrailBoss has an application for shotgun shells but you will find out in a reloading manual.
I understand that primers and powder are hard to find lately. Wads can be found from Graf & Sons website at a pretty reasonable price. Purly makes some nice shot. Hulls are a matter of preference. I have good luck with Remington STS. Some folks like Winchester AA hulls. Most prefer smooth hulls, but I'm not certain that's a big deal.
Good luck!
p.s. Get a reloading manual first.