Sooner or later you need to know some things about bicycle chain repair. This comes handy one day when the chain has to be fixed. Go to a bicycle dealer and get this special tool you need for that.
It is easy to do. Just watch these videos and and think about it for a while. Then get this tool and try it yourself. You will be able to do it yourself, I am sure. There is no need to bring your bike to a bicycle dealer and pay for getting your chain changed or fixed.