1. You will need to know the amount of both stimulus checks you received--last summer/spring plus the one issued right at the end of the year or first of 2021. You can check the status of your payment on the IRS website--https://www.irs.gov/coronavirus/economic-impact-payments
If you did not received your stimulus money or did not received the full amount (maybe your situation changed in 2020) then you can file your 2020 tax return with the Recovery Rebate Credit. NOTE: If your situation changed and you would now be entitled to less (you made more or lost a dependent on your return) you do NOT have to pay back the amount.
2. If you qualify for EIC there are special rules to allow the use of 2019 or 2020 income when calculating this credit.
3. Business owners will be allowed to write off expenses that were paid for with the PPP or EIDL grant. This was a change from previous statements from the IRS that said the amounts were not reported as income but the expenses would not be deductible.