I tried to open the device and take the screen off (it was my sister’s phone), she wanted me to stop and I barely had it...

You may have replaced some screws in the wrong places. The screws holding down the shield plate for the screen plug ins need to be put in the exact place they came out as they are different sizes. If you put them in the wrong place, you can break the logic board, which could lead to the problems you are having.

What happened was I partially separated the bezel from the glass, so I had to replace the entire screen.

Your printer software should have the option to clean the print head. Try that.

Take it to an Apple Authorized Service Provider. They can run diagnostics on it to determine why it loops. Find an Apple Authorized Service Provider at https://locate.apple.com/pr/en/