Support is a very relaxed role. High skill players pivot from bot to other lanes when needed. Most of the time, you will be bot lane for beginners. Support players can either pick tank or healing champions, or even executing champions that share their spoils with the bot lane partner. Anything to help bot laners secure kills while down there. The other role Support players have, is warding. Getting vision on a map that is 90% invisible is crucial. You never know what is in the shadows.

During the first 30 second of the game, you will be waiting for minions and monsters to spawn. The pictures shown are where a bot laner and support would usually wait for minions and get vision on the enemy.

CS means combat score, and you gain cs by killing minions or monsters. CS only counts by killing, not damaging, because an ally minion or champion can steal the kill. CS will grant you gold. You can think of CS as last-hitting a minion for the gold. Otherwise it will be wasted and no one, or someone else, gets the gold. You want that gold because it stacks up. Only difference is you are helping Bot by last hitting the cannon minion.