I am amateur who basically only uses my fists and I want learn a foot work (note: currently I don't know any footwork) so please recommend a footwork which helps me become swift
The question is pretty broad, but I think I understand what you're asking.
The main thing to realize is that footwork is absolutely essential to a good defense. Why?
For the complete answer, read my answer at the following link first:
The gist of that answer is that it takes time for people to react to anything happening. As much as a whole second. That's an eternity in a fight. So if you move, it takes time for your opponent to react to that change. If you stand still, he can target you perfectly. But as soon as you move, it forces him to recalculate where the target is and how to get there. That can stop his attack in mid-flight. Great news for you!
That's why body movement is the most crucial aspect of defense. And notice I said "body movement". That doesn't necessarily mean you have to take a step. You just have to move your main targets in unpredictable, hard to track ways. There's plenty of things you can do besides step.
So that's the principle. As for the techniques themselves, you have a vast library of information available to you: videos of prize fighting champions. People like Muhammad Ali, Sugar Ray Leonard, George Foreman, Manny Pacquiao, Joe Lewis, etc.
Go ahead and study their footwork / body movement carefully. And in your sparring, see if you can make it work for you. If after several attempts you're not getting good results, move on to another style of footwork. Do this until you've found something that matches your personality and physical attributes.
Bruce Lee is said to have done just that:
You don't have to do this on your own. A good coach / instructor has mastered a bunch of different styles of footwork and can work with you to refine yours.
Once you do find the movement style that suits you, it helps finding lots of different sparring partners, each with a different style. That way, you'll expose your weaknesses. And from that, you'll adapt to it and get better.
Hope that helps.