When learning programming languages what kind of projects/information sources do you all find most helpful?

I'm working on learning more about C++ currently for use with Unreal but other than books I pick up here and there not sure what else to try my hand at to help expand and strengthen my knowledge. This can be applied to any language that's just my current focus.

I know typically most people seem to have a decent grasp on what they're working on in here but I consider myself a novice.

Sorry my first post was a question. Been a lurkers on and off for a bit.