Laptop screen gray / green / purple?

I just wanted to start my laptop and then the screen would turn green, then shortly purple and now he is completely gray, someone knows how I get away

this is how the screen looks

This could be a damage to the graphics card. Unfortunately, I have no idea if graphics cards on laptops are just onboard.

As @ traffic light writes, probably defective graphics chip.

How can I test this?

Connect external monitor. If that goes then it is probably not a defect on the chip.

Then it may rather be the display or the connector that leads from the board on the laptop to the display (cable). It will not be cheap to replace something like that.