1999 Cadillac Concours Over heating- leaking anti freeze &a

You have a couple of different issues. The cooling system would require pressure testing, and a check for combustion gases in the cooling system is always advisable. The oil leak could be from many things, drain plug, filter, cooling lines, lower crankcase half, rear oil seal, valve covers. Pretty much any gasket that is sealing oil in the engine. The oil life can be reset on your drivers info center.