After you file

IRS website for unemployment compensation FAQ's - https://www.irs.gov/newsroom/2020-unemployment-compensation-exclusion-faqs-topic-a-eligibility

 

You're eligible to exclude the unemployment compensation if it was received in 2020 and your modified adjusted gross income (AGI) is less than $150,000. The modified AGI for purposes of qualifying for this exclusion is your adjusted gross income for 2020 minus the total unemployment compensation you received. This threshold stays the same for all filing statuses, regardless of whether you're married and file a joint tax return (it doesn't double to $300,000).

To determine if you're under the $150,000 threshold and qualify for the exclusion, subtract all of the unemployment compensation reported on Schedule 1, Line 7, from the amount of your AGI reported on Line 11 of Form 1040, 1040-SR, or 1040-NR.

If you're eligible, you should exclude up to $10,200 of your unemployment compensation from income on your 2020 Form 1040, 1040-SR, or 1040-NR. This means up to $10,200 of unemployment compensation is not taxable on your 2020 tax return. Unemployment compensation amounts over $10,200 are still taxable.

If you're married, the exclusion can apply to you and a separate exclusion can apply to your spouse. If you and your spouse file a joint return and your joint modified AGI is less than $150,000, you should exclude up to $10,200 of your unemployment compensation and up to $10,200 of your spouse's unemployment compensation.

 

The exclusion is reported on Schedule 1 Line 8 as a negative number.  The unemployment compensation received is on Line 7 of Schedule 1.  The result flows to Form 1040 Line 8.