Togapi evolves with friendship. So you have to make Togepi as happy as possible and then level it up in order for it to evolve. There is no set level.
you have to trade it to evolve.
In Pokémon LeafGreen, Magnemite will evolve into Magneton at Level 30.
Level 31.
Level 38.
level 28
at level 40
Level 32.
level 26
at level 36
Level 36.
Rhydon, in Pokemon FR/LG, does not evolve.
Level it up to level 16, and it will evolve into Kadabra.