The IRS will make the adjustment for you automatically if you filed before the legislation was enacted. The IRS asks that taxpayers do not amend.
For more information, see: New Exclusion of up to $10,200 of Unemployment Compensation | Internal Revenue Service
If you did not file yet, TurboTax will automatically give you the $10,200 exclusion when you enter your 1099-G for unemployment. You do not have to do anything to get it. The exclusion will appear on Schedule 1 line 8.