The electrical box has 2xblack, 2xwhite, 1xred and 1xblue. How do I connect new light fixture with 1xwhire and 1xblack?

I would go White to White and Black to Black.

Use a VOM to test which hot wire is switched. Then connect it to the light black and white to white. Blue is a bit strange in a supply box.

Are you located here in the U.S.A.

The wiring you are describing suggests that you are in Europe.

Are you located here in the U.S.A.

The wiring you are describing suggests that you are in Europe.

More than likely. He said he only had a black and white on his fixture he is going to hook up.

The presence of the Red and Blue conductors is what is troubling me, particularly if this is a residence.

I can understand the presence of a red conductor if a switch-loop is involved, but the blue needs to be explained.

The presence of the Red and Blue conductors is what is troubling me, particularly if this is a residence.

I can understand the presence of a red conductor if a switch-loop is involved, but the blue needs to be explained.

Most newer house rooms are wired with a 3 wire circuit circuit through 2 switches so you can hook up a fan with a light and fan circuit. Our house, 8 years old, has a double switch in every BR and the LR. White, black, red. Blue is the confusing factor unless someone added another wire for a separate fan light which is usually blue.

It would really help if the OP would respond and let us know what is actually there.

Was there a fixture there before?
Hook up the new one the same way.