If your oil is leaking that might be a serious problem. That is not something you can do on your own. My advice to you is to go mechanic and fix that as soon as possible.
Leaking oil is not that big problem but it is the problem if it leaks from brakes. It may be problem with your safety. If to much oil leaks than your brakes will become useless. Trust me, for your safety would be better if oil from engine leak.