My 10 year old is into gaming. I'm considering getting a set of components so we can put together his own game rig. Nothing fancy, just a starting point. 

Anyone done this? Thoughts on components or general approach? I'm a lifetime mac user so have never built a pc. Seems straightforward though, right?

Steam Deck is remarkably good, especially for the components/price/usability.

Putting together a gaming rig sounds like a fun father son activity

Seconding shazow’s recommendation of the Steam Deck. It’s a great starting point for a gaming PC. It’s portable and also supports peripherals

Searchcaster