I've been playing that game for about 8 years. (Onlyforyou28 in-game nick) I wasn't know tanks, abilities, roles, what they capable of. I've learned all of that experience playing the game. But it takes so much time. This situation can make people stop playing that game. Cause without knowing your and enemy's tank you can't handle the game. Their penetration stats, weak spots, mobility, accuracy. Everything you know makes you one step further against the enemy.
So I prepared the best tanks, tank destroyers, heavy tanks, medium tanks and artilleries.
It takes 8 years of gameplay to learn them.