Chosen Solution
So I got liquid damage in my MacBook. At first it looked like a total loss, but I realized that after I took the battery out, the MacBook would work while connected to power. This made me think the problem was the battery, so I bought a new one. I put the new one in and waited it to be depleted (was told to do so by the store-owner), but when I plugged the power cord, my MacBook wouldn’t charge. It does show a “charging” icon, but no matter how long I leave it connected to power, it simply won’t charge.
I’ve tried resetting SMC, PRAM, etc. but it still won’t charge.
Leave the battery and charger unplugged. The problem is most likely that the liquid got onto the logic board and has caused corrosion on surrounding components near the charging chip and some other power management chips. You could try cleaning the corrosion / liquid on the board with some isopropyl alcohol brushing. I’m sure there are others here that can post a guide on how to handle liquid damage on electronics.
