There is no statistical data as far as habits (eating and otherwise), of people who play the UFC videogames.
So to answer your question, there is no way to tell.
Noodles are very popular, it's a safe bet that video game players eat noodles.
You are going to learn fighting techniques utilized in the sport of MMA.
I have only taken a few MMA classes, they have been very good.
Yes, it can help you get fit and toned, as long as you combine it with the proper diet.
One that is close to your home, that you can take as often as possible, under a good instructor.
Check out martial art schools in your area, try at least one class and then decide.
When done with the proper technique, it can be.
If you teach yourself, you will not learn proper technique you will not learn any self-defense, and you will not be able to stand up for yourself.
You need proper instruction under a qualified teacher to correct your mistakes, and sparring partners.
That would depend on your natural weight when you are ready.
You are ready once you start MMA training, since you have not even started, it's impossible to tell.