I feel you. I had the same thing happen at level 10, it’s a rough one. I was stuck on it for a whole 3 months just doing my reviews because it all felt like too much. We wanna get you to a place where you can start consuming media asap to help with motivation and overall enjoyment. My recommendation is to start learning common vocabulary outside of WaniKani to get you ready to be able to start immersing. WaniKani is great for kanji, but the vocab it introduces is limited. I also went through Genki I and II early in the game, but tbh Tae Kim’s grammar guide was just as useful and free (but maybe my opinion is skewed because I read it after Genki). However, being able to read the passages in Genki was super rewarding. Tae Kim has this too but the readings are much shorter.
Personally, I used Anki along with this N5 sentence deck. The sentences all use super basic grammar to start getting you used to it and will teach you lots of common words. Anki can be overwhelming to figure out if you’re new to it, so don’t hesitate to ask for help!
Whenever you feel ready, pick some media and jump in! My first book was レンタルおにいちゃん and I only just read it at level 11 using the bookclub resources like @ChristopherFritz suggested.