There is nothing special you need to do if you are disabled. You still report taxable income and pay taxes.
There is a small credit if you take early retirement and receive taxable disability pay, but it is income limited and not everyone qualifies.
https://www.irs.gov/credits-deductions/individuals/credit-for-the-elderly-or-the-disabled
Are you sure you need to amend?
How did you file your 2020 and 2021 returns, with Turbotax installed on your own computer or with Turbotax online? Here are the general instructions.
https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-change-correct-return-a...
