For most people, for that particular change, there is nothing you need to do, since it usually doesn't affect your income taxes at all.
The BUT is this. IF you worked for more than one employer in 2020, and IF the total $$ withheld for SS in box 4 of the different employer W-2 forms adds up to more than 8537.40, then you could file an amended tax return for 2020, and get a refund of the excess SS withheld that was over 8537.40. (if married, this only applies to your own W-2 forms. Each spouse's W-2 forms are considered separately)
If box 1, box 2, box 16 or box 17 didn't change, then you generally don't need to do anything. This is a result of the temporary suspension of social security taxes during the pandemic. Your employer caught up on those suspended taxes, and has to issue a corrected W-2 to show the final amount collected. It doesn't change your income tax return and you don't need to file an amended return.
The only time you might need to file a return is if you worked for more than one employer and your total wages were more than $132,900. In that case, the catch-up withholding and adjustments might have resulted in you paying too much social security (FICA) tax, as described above.
Note that the W-2c for 2020 does not affect your 2021 tax return in any way. You do not do anything on your 2021 tax return under any circumstances. If you have to do anything at all, it is to file an amended return for 2020, and that is only in the one situation that Critter-3 described.