There is a coolant leak from the engine head gasket.
Head gaskets can leak in several ways. It can be an external coolant or oil leak, coolant can leak into the combustion chamber and vise versa, and coolant can leak into the oil. This is not a repair to delay. Coolant in the oil or overheating an engine can ruin an engine very quickly. I would have a mechanic locate and repair any coolant leaks to prevent any further damage.
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