Never played DOTA honestly never really heard of it till I started this game. Though i really need some advice on how exactly to play I mean outside of k/d/a I really wanna know what goes through your mind of how to leave your lane or what counts as success or failure. I losy like 10 games in a row today.I sucked hard some of them thats for sure but others I was best on team in k/d/a anyways.

You have a small priority list while playing, and there's no real right or wrong way to play as long as you can follow them.
1.Protect your towers
2.Destroy theirs
3.Don't die
4. Deal the killing blow on minions
5.Kill enemy champions
6.Control neutral buffs, dragon, and Baron

In the meta-game
1. call missing persons from the lane, anyone not in your vision is a threat to your other lanes
2. don't push any lanes while a team is missing and ward as many choke points and buffs as you can within the jungle.
3. time buff respawns
4.any advantage, no matter how seemingly small is an investment towards the rest of the game
5.Just because you're legendary, doesn't mean you're unkillable.

Follow those steps in summoner's rift, and you'll tend to win, try to think whether or not an exchange is worth it. You know sometimes ideally, you should save everyone and ace the entire enemy team without being scathed, but that's also unrealistic, you have to often calculate the risk/reward, and see who will come out on top in an exchange. It's unlikely you'll 1v5 and ace a team, and it's bad to try. It's arguable, but you can trade a dragon for top tower, and it would be considered a larger gain for your team as a map advantage.

Success is
*getting farmed from minions
*getting champion kills
*getting towers

If you can do these without dying you're good. Some side objectives are
*getting dragon
*baron nashor
*neutral monster buffs

these will help the top objectives become more easily accomplished. You can leave your lane if it's not going to get pushed to your tower or if you're in a 2 lane if your partner can 1v2.

What are good times to buy wards cause i never see them on the map unless I buy I can't spend all the money on wards can I?

To add onto the first two great posts;

Summoner's Rift has a large reliance on teamwork. Try to do your best to keep up the morale if you're losing. Just because you're not farming the best or you've died a couple times during laning doesn't mean you can't make some great plays by paying attention during team fights. We've all been there.

Also, the amount of global money your team has achieved will give you a huge advantage through better items. Always get dragon when it's up and work on last hitting minions.

Map awareness wins games. If you keep the river warded you'll know if the other team is going for dragon/baron and you can initiate a team fight and steal it from them. Warding prepares you to defend ganks too.

A ward is two minions and a small amount of game time's worth of gold. If you're support you should be buying them constantly. Though, all champs from carry to tank should be buying at least one whenever they back. They're worth way more than their cost for the map awareness they give you.