[magnets]

It depends on what you want to use CAD for.

If you want to lay out the robot and figure out angles/sizes for shooters, arms, etc, I'd focus on working with assemblies and sketches to figure out geometry. It's a great skill to have.

If you're drawing up parts to be machined in house without CNC equipment, I'd work on creating good drawings. You need to know and indicate which dimensions need to be accurate (stuff like press fits) and which don't matter too much (lightening pattern).

If you're drawing parts to be machined with CNC equipment, focus on methods to make pockets as well as general design methods to make the common FRC aluminum plate with holes in it.

If you're interested in more advanced stuff, you can look into FEA. In FRC, teams often dismiss FEA as being too difficult and too complicated. While it is very difficult to do a perfect setup of all the forces your robot will experience and interpret the results, it can be helpful to use it to compare two different design ideas to see which is stronger. It is very powerful as a comparison tool, even if the forces you input are not accurate. Also, it can point out weak areas pretty effectively.