Chosen Solution

Today I got a very small amount of milk on my Mac, thought nothing of it and wiped it off and when I got home I put it on charge, I now realise there may have been some liquid in the usb c port as it now won’t charge, any ideas as to how I could fix this from home?

This is tricky! Is the damage limited to the port board MacBook Air 13" (Late 2018-Late 2020) USB-C Board or did the damage jump to the logic board. See if replacing port board fixes things if not this will require someone with deeper skills to fix your logic board or replacement MacBook Air 13" Late 2020 USB-C Board Replacement Here’s the logic board guide MacBook Air 13" Late 2020 Logic Board Replacement