I am having problems with the brakes,the pedal goes to the floor. on 1999 Chevrolet 2500 Pickup

wondering if worn brake pads will cause the pedal to go to the floor? also how do i bleed the brakes on the truck, that may be part of the problem?

Asked by for the 1999 Chevrolet 2500 Pickup
Does the master cylinder still have enough fluid in it? Any warning lights on in dsah?
the resivuor is full,no lights are on in the dash. the place i got the truck replaced a line that was damaged, i dont think they bled the brakes properly, was wondering how to do it.