Where are the freeze plugs on passenger side of.

Freeze plugs or core plugs are located on the block, you will need to strip what ever is covering them, manifolds, exhaust etc to get good access, to remove use a punch and knock in one side but not all the way so the plug falls in to the cooling jacket, with it pivoted you need to pull it out with pliers, they can be tough, you do not want them falling into the cooling jacket as they will block circulation. Clean the hole of any muck using emery paper, normally the plug hole has a slight taper on the out side, position the new plug and I also smear some sealant on it as well, over the opening using a socket that is not tight to fit but close to the size, knock the plug in until it is level with the bottom of the taper and ensure that it has gone in square. Try and purchase brass plugs as these will never rust, they use steel plugs as they are cheaper during manufacturing the engine.