How old are you?
Have you seen the FAQ section? Seriously, it's a lot of information to digest, but 90% of what you want to know is there.
Where do you play?
Be prepared to drop a load of cash, you need at least 500$ to sit at the airsoft table in Canada. 800$ buys you a complete but basic setup. 1000$+ and things get really interesting.
Sniper for a newbie is a bad choice, it's not like in the movies. Tried it once, sold the rifle after that.
Don't order from american site.
Buy eye protection of decent quality first, a decent battery and charger second, then the gun.
Lurk for a week, read the FAQs, then come back with other questions.