Complete the latest level and the next level will be unlocked.
Bulbasaur evolves into Ivysaur at level 18 and into Venusaur at level 36.
level 20
Level 20
level 25
36
kakuna
60
16
at level 16
It evolves at level 22.
It evolves at level 36.
I think it Evolve In level 100