It is really hard, with al the soldering and print etching and what more.

The sad part about that is building a PC is easier than ever. I hadn't built one in over a decade and was shocked to find out that everything is toolless and just snaps right into place! The only part that's maybe intimidating for newbies is putting the thermal paste down without making a mess but even then, you just go slow and take your time and you'll be fine.

none of them have ever built a computer. They seem to think it’ll be really hard.

Depends on what you're starting with. If you mean assembling a case, power supply, motherboard, processor, RAM, storage, video adapters, etc., the only difficult part of that is deciding you can do it.

If you're talking about assembling components on a breadboard, that's going to be more challenging.

I've done both. The breadboard computer was for an electronics class in college. It was both more fun and more pain.