I'd say see wot the fluid is.

Smell like gas?
Thick like oil?
Tastes like ethlyne glycol? (Just kidding)

I'd look down the carb n see if it's flooding first.

You can do a coolant pressure test if you have the pump for it. That'll tell you if your loosing coolant. And for external you can see where.

If it's ending up in the oil pan or cylinder then I don't need to tell you what to do.