Woo! Congrats on Level 2!
I schedule my reviews for three times a day: 8AM, 2PM, and 8PM. If I can’t get to all three, it’s not a huge issue, but I like having set times to sit down and work through my reviews.
I do 20 lessons a day (if I have any available) on top of that, but you can choose however many you like. When you hit a level like you just did I’m sure you saw a HUGE pile of lessons waiting for you full of new radicals, kanji, and vocab. Don’t feel pressured to do them all at once, and only do your lessons when your review pile is clear.
In addition to Wanikani I am working through Japanese From Zero Book 2 as well as Tae Kim’s Grammar Guide.
Your learning plan is entirely up to you but you should aim for a bit of reading, writing, listening, and speaking if you can every day.