No it's not iOS for iPhone and iPads. It's Mac OS. You can't install the Desktop program on a mobile devices like a iPhone or iPad. You need to update your Mac.
If you can't install the Desktop program, you can use the Online version. Or find another computer (Windows or Mac) to install it on.
MAC system requirements,
https://ttlc.intuit.com/turbotax-support/en-us/help-article/product-system-requirements/minimum-syst...
If you need to use the Online version this year. If you used the Desktop program last year here’s How to transfer into the Online version, expand the blue link if you used the CD/download last year
https://ttlc.intuit.com/community/entering-importing/help/how-do-i-transfer-last-year-s-return-into-...
If you used the Desktop program before you may notice several differences and not like the online version. It has less features and no Forms Mode. You can only do 1 return. Your return is only saved online so be sure to save both the .tax2023 data file and the pdf file to your computer when you are done. In case you need to amend in the future or if you need a copy to get a loan or something. You might not be able to access your online return when you need a copy.