It’s hard to quantify how many you should do.
Some kanji will stick immediately, some will take much longer.
One of the first methods I was using back in the days was recommending 5 per day, but I really think there’s no “one size fit all”. Still it’s a reasonable pace at beginner level, and can be increased later on.
You should probably use an SRS system to keep track of what you remember and what you don’t; slow down when the “don’t know” pile gets too high, and speed up when you feel like it.
Since you are here, the obvious answer would be to just go with WaniKani, but you don’t have to.