My car won't shift into 3rd gear all the time but not sure if the transmission is totally blown?

You seem to have a major leak to have to add a couple of quarts of fluid. You may have burned the bands up. Try this first. Try adding a bottle of Trans- Medic or about a half a bottle of brake fluid plus Lucus Trans leak to your transmission. You need to find the leak, Could be the front or rear seal or one of the cooling lines to the radiator.