I was asked to do a task which My boss could not do. After I did it, my boss asked to show him how to do it. In the past, I have done that for him, but He turned around and get the credit how is done.

Henriquez, do you have a question?

I always do tasks from my boss and He always asks me how I did them so He won't look bad in front of his superior. After I showed him how I did, He turns around and take the credit for doing it. Is this correct?

Maybe it's not correct but many of them do it...get used to it or stop doing it for him if you can.

I agree... its called deligation... you do the work and they take the credit. Bosses everywhere do that. Always have... always will.

I had a boss that, whenever you would suggest something to him, like a way to do something or a new process, he would say "no" and then give you a reason it wouldn't work. In meetings, he would then say essentially what I had said and it was then his idea. I learned and stopped giving him ideas.

I had a job that gave out cash awards for new ideas, and yet if anyone had one, the bosses said they weren't good ideas, and wait a week or two, and implement them themselves.
You want to 'do' something about it? Go ahead. Plan on losing your job.
What I would do: Keep a small notebook of what it was and when - precisely.
When the job market improves, look around for new jobs... and go to that same boss and take the plunge. Tell him you want a raise and a promotion, and start reading from your notebook. How you handle it will either get what you want, or it will get you fired. It takes a lot of skill.

One - you record what your boss did or said
Two - look for new positions within the company first, then outside

It is an uphill battle, please don't spend too much time to fight with him or tell his boss...

This is how the business world works, hopefully as your boss moves up, you move up with him.