You have to learn by doing. Here’s a good tutorial for Fusion 360 -> https://youtube.com/playlist?list=PLISvF10lebIzMQjtPhKVlCwzs...

And a classic for Blender from Blender Guru -> https://youtu.be/4haAdmHqGOw?si=7Sk-dxbyPFi5PL8u

I’m no expert but the little I know was trying to solve one problem after the other.

Thank you!