It might be tough at your grammar level, but try the absolute beginner book club if you’re interested in native material a level up.
Also for graded readers check out the tadoku free stuff. There’s quite a few covering a pretty wide skill range. Japanese Graded Reader Difficulty List | Natively
Personally I’m a huge fan of Satori Reader, but I think it’s better off for people around N4 and WK 25.