Clefairy cannot evolve into Clefable by leveling up in Pokemon FireRed. The only way to evolve Clefairy is by using a Moon Stone on it.
pidgeotto will evolve at level 36
Ghastly will evolve at level 20.
To get Clefable in Fire Red you need to find Clefairy in Mt.Moon then get a moon stone(you should level it up first). Go to your bag and find the moon stone then use it on Clefairy, then you get Clefable.
At level 33.
You can't see it, evolve a clefairy to get clefable.
Clefairy cannot evolve into Clefable by leveling up in Pokemon FireRed. The only way to evolve Clefairy is by using a Moon Stone on it.
Clefable can't evolve.
Lickitung does not evolve in FireRed.
Yamna does not evolve in FireRed.
In Ruby, Sapphire, Emerald, Colosseum, and XD you trade from Firered or Leafgreen In Firered, Leafgreen, Diamond, Pearl, Platinum, Heartgold, and Soulsilver evolve from Clefairy
Dragonair will evolve at level 55.
Rhydon is not able to evolve in FireRed.
Electabuzz is not able to evolve in FireRed.
Rattata will evolve at level 20.
pidgeotto will evolve at level 36
Ghastly will evolve at level 20.