Dry up breastfeeding

I'm scared my milk will dry up. Or decrease dramaticly I was told pumping will make me dry up. But how is it any different from baby taking my milk and increasing my milk? I worry that my milk will dry up and we will have to feed her formula I don't know why but I am not willing to give my baby that stuff at all I do not want her ever taking it I love breast feeding my baby. Will I dry up ?