TL;DR any level is fine, it will be hard, start easy and ideally pick something from the ABBC (past or present) to make it easier.
I’d recommend a very low goal that you can force yourself to stick to, as it will be a slog.
After each concrete wall, there will be another hurdle.
I’d personally highly recommend reading along with the Absolute beginner book club, even a past thread is fine, as that way there are shared vocabulary lists published and threads where people discuss the grammar points and where you can ask for help if needed.
Some ABBC books to consider:
past しろくまカフェ with vocab list - I think this is on the harder side of ABBC due to puns and such
past チーズスイートホーム with vocab list
most recent past からかい上手の高木さん with vocab list and ongoing offshoot club
current (started July 10th) それでも歩は寄せてくる with vocab list
next (starting September) 大海原と大海原
On a good day I can do a few pages of からかい上手の高木さん but for the same effort I seem to be able to read a chapter or more of チーズスイートホーム, so the manga you pick will make a big difference in your pace. I’d recommend starting out easier and ramping up if possible.
OTOH, something that interests or excites you might give you the motivation you need, depends on your preferences.
I cannot +1 the absolute beginner book club enough
I’ve been very slowly reading my first manga (からかい上手の高木さん) with the help of lovely people such as @ChristopherFritz and @shuly =D
(and many others, only naming people who have been in this thread)
FWIW I’ve been working through the ABBC’s からかい上手の高木さん despite having not quite finished Genki I, largely because I find textbooks quite difficult to stick with.
If you are making progress with a textbook then stick with it, as it will make things easier. For me at least grammar tends to be much more of a blocker than vocab when reading manga.
If you get stuck, ichi.moe can be great for giving hints, although it does make mistakes.
If you give ichi.moe Japanese, it will try its best to break it down for you.
For example here we can see Ichi breaking down 持ってない into 持って + いない
and it then explains that 持って is the te form of 持つ “to hold”, and いない being the non-past negative of いる “to exist (animate)”.