One of the biggest changes was for unemployment. Did you get any unemployment?
If you filed before the $10,200 unemployment exclusion, the IRS will recalculate your return for you. There is no need for taxpayers to file an amended return unless the calculations make the taxpayer newly eligible for additional federal credits and deductions not already included on the original tax return.
See this new IRS announcement May 14, 2021
https://www.irs.gov/newsroom/irs-begins-correcting-tax-returns-for-unemployment-compensation-income-...
You may need to amend your state return
https://ttlc.intuit.com/community/state-taxes/help/do-i-need-to-amend-my-state-return/00/2134732
