Sorry you need Windows 8 or higher to install 2020. Window System Requirements
https://ttlc.intuit.com/community/system-requirements/help/minimum-system-requirements-for-turbotax-...
You will have to find another computer or you can use the Online browser version.
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 .tax2020 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.
Start an Online return here,
https://turbotax.intuit.com/personal-taxes/online/
