You can in the Desktop CD/Download program. But you can't install it on Mac OS 10.10.5. If you can upgrade you Mac or find another computer buy it here,
https://turbotax.intuit.com/personal-taxes/cd-download/ Online is only good for 1 return. But you can use the same email address for 5 accounts. How to start another return in the Online version
https://ttlc.intuit.com/replies/3288574
