Charizard is one of the rarest and strongest Pokemon in Pokemon GO, making it easily one of the most sought after. He can be seen in the wild, albeit rare, but by increasing the amount of Charmander Candy you have and evolving the basic Pokemon, you can add him to your collection.
You will need to evolve Charmander into Charmeleon, and then the latter into Charizard. For this you will need a good deal of Charmander Candy. There are three simple ways to get more Charmander candy.
First of all, you should catch as many Charmander as possible. If you know where to find them, go there and catch as many as you can because each one you catch will give you three candies. Fire types don’t seem to inhabit any one area over another the way water and grass types do, so keep your search wide.
Secondly, if you have caught a lot of Charmanders or Charmeleons, you can transfer them to the Professor and get one Charmander Candy for each. Do this with all but one of each Pokemon to get as many candies as possible from transferring, whilst leaving yourself Pokemon to evolve.
Finally, you can hope to find Charmanders in two kilometer eggs. Eggs will often award you Candy along with a Pokemon, so keep incubating those eggs and keep walking.