I used to use fusion for many years.

Recently I transitioned to freecad. There was a bit of a learning curve since it is more constraint based than fusion requires. Once freecad 1.0 came out for prerelease use I started using that instead...it is much improved over the old method. A lot more similar in use to other CAD packages.

I suggest finding a few good tutorials and working through them...it took me a lot less time to learn freecad (for me) than it did to learn fusion...and it removed one more closed step in my mostly opensource toolchain.