How one can remove cavities of tooth?

I'm no dentist but in these type of circumstances i would seriously consider a dentist to answer this one but the cavity can turn into gingivitis. My sister had a cavity on her tooth, of course she was only 9 so she would lose it. Your teeth or tooth may hurt but you did it to yourself. if you really need to get rid of it then seriously consider brushing you teeth more, less sugary food, and no more fats. I HOPE THIS HELPS :)

P.S. I'm only 11 :) very smart