Hey, first of all welcome to CardsChat!
It is important to know what makes you tilt. Is it a bad beat? Lack of concentration? Did you make a bad move which made you tilt? If you want to improve your concentration, focus and less tilting i advice you to look in to the mental game of poker. There are a lot of video's and things online. For example this one. https://www.youtube.com/watch?v=AyuXKei6gIU
MTT or cashgames?
I think you should try out both if you don't know yet which is the best for you. Those are 2 totally different games. I advice to play both and find out which is works the best for you, and more important, which is the most profitable for you.
Theres a lot of free stuff online to learn poker from. Books, forums, blogs, video's. I suggest to start of with the freestuff and see you how improve.
Goodluck in improving and don't forget to enjoy the game!