State tax filing

The 1099-G for state tax refund would only be needed to enter as income if you itemized your deductions in the Federal return in the years 2018 and 2019. You would have had to itemize your deductions on the Schedule A for the years of the refund.

Look at your federal tax returns for those years to see if you took the standard deduction or itemized your deductions.

If you did itemize deductions on the Schedule A, you will probably need to amend your 2020 return and add this as income, unless the amount on the forms is too push you into the next tax section.