The 1040SR is the same as the normal 1040 tax return. If you are over 65 you get the SR version that just has bigger type. You still use the same Turbo Tax program, either the Online version or the Desktop CD/Download program.
Do you want to buy the Desktop program? You can buy it directly from Turbo Tax or Amazon or anywhere. Look for sales. Costco has a coupon now in January.
Start an Online return here,
https://turbotax.intuit.com/personal-taxes/online/
Buy the personal Desktop CD/Download programs here
https://turbotax.intuit.com/personal-taxes/cd-download/