Most laptops in that price range would be fine. Just make sure it has SSD with plenty of storage for her and at least 8GB of RAM. Careful on screen selections and make sure you get at least 1080p resolution. If color is important, you might want to make sure that the screen has 100% sRGB or at least 72% NTSC. There are OEMs slipping in inferior screens in this price range so watch out.
As for models, HP Envy/Spectre models are great. Alternative is Lenovo Yoga/Ideapad, as they tend to give you more bang for the buck.
If you want her to embrace the post-PC era, Samsung Galaxy Tab with a keyboard is actually not bad. I myself am replacing my old laptop with a Galaxy Tab S7FE. And imo it's more flexible than ChromeOS.
You can upgrade the RAM/SSD on many Windows laptops which means that you can start out with low specs and upgrade if they aren't enough.