Avoiding Chromebook. Good for some things. Not sure about this. Problem is, *I* don't know anything about them, and part of my plan is to help her learn some Arduino programming (C++). I know how to root around in folders on C drive, but Mac and Chromebook, not so much--and I have no incentive to learn them.Jeffkeryk recommends the Chromebook and he seems to be a tech savvy guy with lots of computer choices. It might not be what the OP needs but I would look closely and think carefully about that decision.
Made the mistake of downloading Arduino 2.0 IDE onto the wife's PC, and quickly ran into the problem of, it doesn't match the tutorial that came with the Elegoo starter kit. And I'm not used to 2.0 either. Got the 1.8 that the tutorial uses, and that I'm used to, and suddenly I'm useful again. [Plus 2.0 does the classic problem of, fix one thing by breaking another. So she's already learning the ropes: only upgrade your tools when you have to!]