I was fired because the managers said that I was over herd by a guest asking someone to not talk about me and to please stay away from me and come to find out it wasn't a guest it was a coworker who said he herd it and he didn't hear anything and now he is running around telling all of the other workers that he is the one who got me fired and that he sleeps better he is telling guest that call I got fired and will never work for the company again. The general manager is pulling my former coworkers aside and tell them they can't react about me being fired. I also was going to join some friends there for a drink and they were told I can't dine there.

What kind of business?
How many employees, do you know or estimate?
Did you get a statement in writing of why you were fired? If so, what does it say? Your story is a little hard to follow.

It is a restaurant and there are about 70 + employees there and no I didn't get any paper work on why I was fired I have a copy of the write up on Sunday AMD that is it. I have been employed with this company for several years also and have never gotten.into any kind of trouble there

Your first response was fine.
Can you explain the incident (that either did or didn't happen) a little more?
Also what state the business is in.

Regarding not letting you enter the place: they can prevent anyone they want from entering unless it's for a civil rights reason such as race, creed, gender, disability.

Also, since most employment is "at will" you can be fired at any time for no reason. Unless you are covered by an employment contract or union, the termination might have been wrongful, but there is nothing you can do about it legally. Basically, this is a he said/she said. The other co-worker reported it, the GM decided to believe them and fired you. Unless you can prove that you didn't say what was reported, which is nearly impossible, there is nothing you can do.

You can ask to meet with the GM tell him your side (if you haven't already) point out that the co-worker was bragging about getting you fired. And see if that will get your job back. If it doesn't move on.

I was fired because ... I was ... asking someone to not talk about me and to please stay away from me ... I also was going to join some friends there for a drink and they were told I can't dine there.

Ok, you were fired because management believed you were being unfriendly to a guest. And because you had a drink with friends at the establishment.

Yes, they can fire you for those reasons, even if it's just an untrue rumor. They can fire you for no reason at all, with certain exceptions. This is not one of the exceptions.