There is something dragging underneath my car causing my tires to leak air and make a grinding sound when I turn left or right.
This is probably something that needs to be looked at as soon as possible. Two likely causes could be the either an inner fender liner that is dragging in the tire or the plastic belly pan has either come loose or is damaged. Either can come loose and possibly dislodge from the vehicle while driving unless they are properly attached. You may want to enlist the help of a mechanic, such as one from YourMechanic, who has the expertise to access the dragging part and who can repair or replace the component. He can also determine the cause of the tire air pressure loss and recommend the proper repair.