There’s also plenty of other graded readers apart from the ones already mentioned, e.g. the ones listed on Natively, ordered by difficulty: Japanese Graded Readers Difficulty List | Natively
And once you’re at the point where you want to tackle your first native content manga, I recommend doing it together with the Absolute Beginner Book Club. You can ask questions, get corrections for translations and read the answers to other people’s questions, all of which massively helps. I don’t think there’s a better way to take the leap into native content, and you’ll find lots of people on these forums who’ve started the “native media” part of their journey there.