how do you add Freon to a 98 cutless oldsmoile. where are the high and low ports

If you haven't found the ports by now they are easy to find. Open the hood and look down and to your left. At the top of the radiator/on top of the cooling fan you will find the high side port. The low side port is at the fire wall behind and below the alternator. It's a bit of a reach to get to it and the vehicle must be cool due to the exhaust manifold proximity.