Ezreal is a good ad carry with some combined ap which helps him to hit tanks when others cant
squishy till he gets trinity
who can fast kill others without being noticed if played well!

I suggest mostly use exhaust because it others others stats and movement which helps you to run away or kill him without much damage taken!flash is a good option but not advised as you already have your e and can jump through walls.So you could try heal if you are new on ezreal or ghost as a result you catch your target before he runs away.

Always try to stay out of range and focus the ad carries or they will focus you as a result their assasins or fighters see you dropping fast and focus you AND ALWAYS LOOK YOUR TEAMMATES BACK!!!

Pros

low cooldowns

high damage at start

easy pentakill with ulti

good spammer

Cons
mana hungry if spamming without blue
squishy
hard to farm at early game
no cc
not easy to master

It isn't easy to farm with ezreal as i said..try to farm from the start of the game take the minion last hits and whenever you are able to farm go on :)
A good way to clear a big minion wave from the other side of the map is to use ulti even if you are there you can do it as when q hits your cooldowns are reseted by 1 sec