Yeah you can do. It will still make beer but it won't be the best beer.
My advice would be if it's your first go at home brewing, you might as well have a crack, but don't be put off by the results. The aim of this is just to practice the method of making beer and getting used to taking hydrometer readings etc.
If you have already made a few batches and are comfortable with the process, I wouldn't bother personally.
Like I said, they will make beer, but not the best beer.