That looks like a kindle maybe a paperwhite 2 or 3? Amazon is making those way less functional very soon. I would recommend looking into jailbreaking it asap and getting KoReader installed so you can keep using it. I have a paperwhite 3, a kobo touch, and now a kobo Clara colour and all of them run beautifully with KoReader and are muchore useful than they were with the default software.
Also, I've heard good things about Dungeon Crawler Carl but haven't read it yet myself. I hope you enjoy it.