the Divorce was on Dec/2019 I know that there is no deductions for any divorce after 2018 but I just want to know what number should I put in the Alimony paid field on the form.
If you enter in TurboTax Online in the Alimony section that your divorce date is in 2019, and enter any amount paid, when you select "done" it will tell you that the amount is not deductible.
Unless you could have deductible alimony from a pre-2019 divorce decree, there is no requirement to record alimony paid in TurboTax.
See this TurboTax article for more information.
Updated Response:
If you enter in TurboTax Online in the Alimony section that your divorce date is in 2019, and enter any amount paid, when you select "done" it will tell you that the amount is not deductible.
Unless you could have deductible alimony from a pre-2019 divorce decree, there is no requirement to record alimony paid in TurboTax unless you live in a state that doesn't follow Federal law on this issue.
See this TurboTax article for more information.