I create modular parts that work and save them as my shapes in tinkercad (I know, training wheels.)
Nothing wrong with Tinkercad, that's how I've made every 3D printed part on every one of my sabers since I started.
...Although, that said, maybe look into something a bit more powerful once you feel you've got a hang of the basics. Tinkercad is surprisingly powerful once you figure out how to use it, but that comes at a cost. I'm good enough at using it that I can run up complex designs (ie, entire sabers) in a few hours, but I've also hit the technical limit of what it can do.
I want to go a bit further and do some stuff TinkerCAD doesn't cover (like fillets on curved surfaces and proper parametric design), so I'm having to learn some "real" CAD software. But the learning curve there is steep enough that 99% of the time, I just make the rough shape I want, export it as an STL, and then work on it in TinkerCAD because it's faster, and I find myself wishing I'd moved onto "real" CAD a lot earlier, you know?