The oil and the antifreeze are mixing together. The engine also sounds loud.
It sounds like your talking about engine oil that has mixed with your coolant, depending on where you find them mixed whether in the engine or radiator would be the first diagnostic information. Coolant in the engine usually means problems can exist in the head gasket but it could be in the lower intake gaskets.
If the engine oil is getting into the radiator I would suspect one of the oil galleys is leaking pressure into the cooling jackets which would warrant a new block. Have a certified mechanic test engine compression as they shouldn't be farther than 15% of another, if that tests out ok I would replace the intake seals.
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