The image on the monitor became sharp, pixelated. What to do?

Question

Fonts

I wanted to connect the laptop to the PC, like a second monitor, I inserted the cord, but nothing happened, I pulled it out and put it away.
Now the image on the PC monitor looks something like this.
I do not know what to write to Google or what to do, maybe one of you knows.

Here is a picture of how my image looks on the monitor now and a screenshot of the screen, maybe everything is fine with you, but my image is pixelated, square

Answer 1

If the screen resolution remains the same,
then in Google you need to write about "font smoothing".