You have liquid damage. How much can only be determined with more exploration. Purchase the proper tools (every job is easier with the correct tools). Study the guide & comments to open your machine so you do not do more damage pulling connectors off the logic board. You will have to look for corrosion and swollen/burned components. Use the tags at right to see what you are in for.
At the least you need a new top case… if you're skilled (and masochistic) you can try replacing just the keyboard and trackpad it's a real challenge.
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