If you have sufficient taxable compensation to contribute -

Enter IRA contributions here:
Federal Taxes,
Deductions & Credits,
I’ll choose what I work on (if that screen comes up),
Retirement & Investments,
Traditional & Roth IRA contribution.

OR  Use the "Tools" menu  (if online version under My Account) and then "Search Topics" for "ira contributions" which will take you to the same place.

IRA contributions after age 70½

For 2020 and later, there is no age limit on making regular contributions to traditional or Roth IRAs. For 2019, if you're 70 ½ or older, you can't make a regular contribution to a traditional IRA.

Check all your entries. Making myself age 80, I just made an IRA contribution. Make sure you had enough taxable income to take advantage of the deduction.