I have a Kobo Clara which is nice for reading and a Kindle Scribe which is nice for writing. Actually I wanted to get (and still want to get at some point) the Supernote A5X, but it's difficult and expensive to get where I live.

My Onyx Boox Leaf 2 is awesome. The e-ink screen really is a game changer, I love it a lot. It's like paper, that you can read in the dark. And it being Android is amazing because I can have all my epubs on it, Hoopla, Libby, Barnes&Noble, Kindle, Kobo, and any other apps where people try to reel you into a DRM ecosystem. Mine can't really do notes I think, but a lot of the Onyx Boox products can I think, and do them quite well from my understanding. They can get pricey though.

Get the Paperwhite Kids. Like $10 more than the ad supported version, no ads, free cover/case, 2 year accidental protection warranty instead of just one year manufacturer warranty. Just be sure to cancel the free trial of the kids service. Also, be sure to never connect it to wifi and just transfer your books through Calibre.