extension for what year? it's too late to file for 2021 and probably too early to file for 2022.
2022 online is not available until December
if you are trying to prepare 2021 that can only be done by buying a desktop version - full PC or MAC . efiling and online preparation are closed for 2021.
what you may have bought is the 2021 app (call support for a refund if you really wanted 2022)
to download 2022 app for desktop installation (laptops work too if they meet system requirements) and preparation here's the link
https://turbotax.intuit.com/personal-taxes/cd-download
however, if what you want to do is prepare online there is nothing to download. you create an account choose a version and start but as I stated online is not yet available.
