There are a number of reasons 'people' cover up a hardwood floor. One of them is the floor is NOT able to be refinished. In other words, it may have been refinished to-the-max. Soooo, you need to find that out.
Now, assuming your floor is 'good to go', read about the entire process to be sure you're up for it. It's a long and dirty job, but if you do it right, it is obviously a work of beauty. But, if you, say, 'gouge' the floor or have bubbles in the finish or forget to tack the floor, it will look horrible and you'll end up calling a pro anyways. And by then, you may not be able to refinish it then.
Go to How To Refinish A Hardwood Floor. There are TONS of sites on the WEB on how to do this job. Each of them has useful insight. So if you know how to Search the WEB, use keywords like 'refinish' and 'hardwood floor' and 'how to' and so on.