Bulbasaur has to be level 16 to evolve into Ivysaur and level 32 to evolve into Venusaur.
l evel 36
You can't find a wild Venasaur in-game. You can get one by: 1.- Evolving your starter pokemon Bulbasaur to Ivysaur and then to Venasaur(Assuming you selected Bulbasaur) at level 34. 2.- Trading Pokemon with a Friend who do own a Venasaur or its pre-evolved forms.
Bulbasaur evolves through leveling up. Beginning at level 16, it evolves into Ivysaur. (Then Ivysaur evolves into Venusaur beginning at level 32). Venusaur is the final evolution of the line beginning with Bulbasaur. If an evolution is delayed (because the wild Pokemon chooses not to evolve, or the trainer cancels the evolution), the Pokemon will continue trying to evolve each time it levels up after the level listed. Holding an Everstone will prevent Pokemon from evolving through leveling up. Don't press B if you want your Pokemon to evolve. That is the button that cancels evolution.
bulbasaur should evolve into a ivysaur at level 16 and then you can evolve it into a venusaur at level 32 you can find out more about bulbasaur if you go onto this link here http://pokemon.wikia.com/wiki/Bulbasaur !!
In Cerulean City, there is a house with a woman who has a Bulbasaur. When your Pikachu's happiness is at a certain level, the woman will offer you the Bulbasaur after speaking with her. If your party contains five or less Pokémon, you can accept. Bulbasaur will be at Level 10.
Bulbasaur evolves into Ivysaur starting at level 16, then Ivysuar evolves into Venusaur at level 36.
10
Bulbasaur learns it at level 41. (Ivysaur learns it at 46 and Venusaur learns it at 55)
Level 46.
level 46
Bulbasaur evolves at level 16.
16 Ivysaur 36 Venusaur