I received a CP2000 Notice from the IRS because I did not report gambling winnings. I need to report those winnings, and also deduct my gambling losses for 2020.

You will have to amend your 2020 federal tax return to report the gambling winnings and losses.

See this TurboTax support FAQ for amending a 2020 tax return originally completed and filed using TurboTax - https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/amend-2020-return/L3XdA1Pw8_US_en_US?uid=l6vacr4q

 

Gambling winnings are reported on a tax return as ordinary income.  Gambling losses are reported as a Miscellaneous Itemized Deduction on Schedule A.  You DO NOT subtract your losses from your winnings when reporting your winnings on a tax return.

If the total of all itemized deductions on Schedule A are less than the Standard Deduction for your filing status then Schedule A will not be used for deductions.

 

Standard deductions for 2020

• Single - $12,400 add $1,650 if age 65 or older
• Married Filing Separately - $12,400 add $1,300 if age 65 or older
• Married Filing Jointly - $24,800 add $1,300 for each spouse age 65 or older
• Head of Household - $18,650 add $1,650 if age 65 or older

To enter, edit or delete Gambling Winnings and Losses -

• Click on Federal Taxes (Personal using Home and Business)
• Click on Wages and Income (Personal Income using Home and Business)
• Click on I'll choose what I work on (if shown)
• Scroll down to Less Common Income
• On Gambling Winnings, click the start or update button

@k.arquines - I assume you have already filed 2020 and need to amend...

 

suggest looking at your transcript at IRS.GOV because I imagine it was reported by the Sports Book so you want to make sure what you report equals or exceeds what they reported on Form 1099-G.   These will get added to income on the amendement form.

 

with respect to losses, they are reported as an itemized deduction and cannot exceed the winnings; if you take the standard deduction, none of the losses are deductible.