How to fix youtube layout

Got 27" screen and youtube look like

Do you mean the video size? Because you have it on the slightly bigger setting. If you look down the bottom right of the video there are three rectangles. You have it on the middle one, but you want the rectangle to the left, the smallest one.

Did you tried opening YouTube in other browsers as well?

or use small player to fix the issue. You are using the large player now.

I mean normally the video screen scale nicely into the middle of the monitor screen. But now it is on the left side.