There are guides on iFixit that will show you how to remove the screen.
[guide|108479]
As someone else said, rice doesn’t really do anything besides make a huge mess. To clean corrosion that has built up on connectors use some isopropyl alcohol (at least 90%) and a toothbrush to clean any corrosion from the logic board. Use a hair dryer after brushing the logic board to get rid of any moisture then attempt to connect the screen again. If the problem still exists then there is likely either damage to the logic board or the screen.