@rohsgx2 this sounds more like a broken screen. Horizontal lines are pretty much always coming from a bad screen. Since iFixit does not yet have a specific guide for this, use the one [https://www.nadiemellamagallina.com/en/manuales/smartphones-1/xiaomi-191/xiaomi-redmi-note-6-pro-880/pantalla-completa-7668|from here] It was written in Spanish so get a browser to translate it for you, if needed. Replacement displays are available at many online stores.
While you work on your phone, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has a device with the same issues as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.
Repair is War on Entropy!