Since you put alcohol under the battery you might have gotten it in the display and damaged it in the process, it can also be a display connector issue, try cleaning it with 99% Isopropyl alcohol. If you can't get any sign of life you might have a broken screen, displays failing after being in contact with water is pretty common. You can get a new display at [product|IF437-035|Samsung Galaxy S20 5G (USA) Screen and Battery - Genuine|new_window=true].