Notebook suddenly defective?

Yesterday evening I was sitting on the notebook trying to make transfers and suddenly the part went out and it could not be started. The light on the side where it is shown that the power supply is attached is no longer working. Then screwed it on and there's a strange liquid all over the notebook that has a consistency like oil but is odorless. I never got anything on the thing so I'm a little surprised. The battery is still working, I checked it with a multimeter, but it no longer works. That the interior with a hair dryer with sufficient distance dried again nothing. Which surprises me a little anyway that only an 8gb RAM bar is installed, but it should have a total of 12gb. I bought the notebook from Media Markt 3 years ago. Maybe someone knows what it can be? I have the guess that the mainboard is over. It is a Lenovo ideapad 320 15 KB.

Clean the mainboard and the fan with isopropanol and see if it works but that looks bad.

Edit: looks like something has leaked and damaged the video bridge.

Are you sure that no liquid has spilled onto your motherboard?

It has 4GB of internal memory, so only an 8GB bar is installed.
Have you ever tried whether it only starts with a power supply, without a battery?
Doesn't he make a beep when he turns on?

Looks like condensation on the cooler.

I'm 100% sure of that

No, unfortunately not only with the power supply. It makes absolutely no noise