First, i know often the answer for a kanji/vocabulary, but i am not really sure if i type in the on oder kunyomi reading…I know that there is a rule about this but it would be perfect if wanikani tells me with the right answer if i typed on or kunyumi reading or tells me in lessons, every time if i type something in what reading i typed.
Like others have said, the first levels are somewhat tough because you have so many new concepts tossed at you. On’yomi? Kun’yomi? It is this way sometimes, that way another?! Stick with it for a few levels and each time you see a kanji / vocab, think about the reading a bit and how it connects to the other readings. By level 10 or so, you will likely have a good understanding of the On/Kun concept and will probably be able to predict the pronounciation of many new vocab words!
Second, the most frustrating part: I know the meaning of 目玉 instantly if i see it…than i have to think for some time about the correct reading. But if someone would ask me, 'Hey, whats eyeball in japanese and how do you write it?", i dont know the answer, even if i think about it. If i look after it, its right clear to me and i asking myself why i didnt know this instantly. So for now i only know the meaning instantly, but cant read it in a text because i dont know the right reading when its not the known vocabulary i learned from wanikani. And if i should write kanji, some are just deleted from my brain for this moment.
I struggled with this feeling, probably still do to some extent. I have gotten a lot better at reading things, but man… speaking… I would be a total trainwreck. But why? Well, I see language as a set of skills I suppose; reading, writing, speaking, listening. Whatever you practice, you get a lot better at! In this case, WK really emphasizes reading. So I think if you only stick with WK, it is reasonable to expect that you would not be very good at the other skills because it isn’t practicing those. Personally, now that I have a decent baseline for kanji and have spent time reviewing grammar, etc… I have been trying to do a lot more listening practice. Just keep at it every day and you will be amazed at your progress.
Okay, now for a word of advice… Don’t worry about this too much for now. You don’t want to overwhelm yourself and burnout. Focus on WK for now, maybe do a little basic grammar, but take everything in stride. Once you get comfortable and have a good routine, then consider supplementing additional things if you feel you can handle it. Eventually you want to get to real material to practice with, but you have to walk before you can run!