Unfortunatly for us, Charizard isn’t a pokemon that can be obtained easily in every game. Actually only a few of them have that possibility, outside the trade.
Red/Green and FireRed/Leaf Green – charmander is one of the starters, so if you choose it, you can evolve it at level 36 to a Charizard.
Yellow – charmander is found on the route 24 and 25
HeartGold/SoulSilver – in Kanto after collecting all 16 badges and defeating “Rival” at Mt. Silver
Pal Park – Field
Gold/Silver/Crystal, Ruby/Saphire/Emerald, Colosseum, Diamond/Pearl/Platinum – must Trade
Black/Black2/White/White2 - Poke transfer
X/Y - Evolve Charmeleon (You can get charmander from Professor Sycamore in Luminose City after battling him)
Alpha Sapphire/Omega Ruby - You can trade it or from the Event (there were a bunch of them over the world)Sun/Moon - Using Pokemon bank