On the keyboard, the abilities are known as "Q,W,E,R". Using your ablilites in the right order and having common sense could lead to a kill in League Of Legends
Wards are usually put into bushes to give you and your teammates vision on the minimap. Vision is very important because it allows you to know ahead of time if an enemy champion is coming to gank you.
Health Potions increases your health regeneration for 15 seconds.