Like many current apps, TTax 2024 is only supported on the current release of MacOS (Sequoia) plus the two previous releases (Sonoma & Ventura). Intuit made no secret of this, they began announcing it almost a year ago.
If your iMac is qualified for Ventura or Sonoma, and you want to keep Monterey, you could consider installing Ventura or Sonoma on an external drive and install TTax 2024 on the external drive. Boot from the external drive in order to run TTax.
In my own case, I skipped Ventura and went right from Monterey to Sonoma. It was a smooth transition and all is working well.
Or, as @dialabrain already suggested, you could use TurboTax online. If you already purchased a license for the TTax2024 app and want to switch to the online version, call Intuit and have them transfer the license to the online version.