Solved
Can the same download be loaded and installed on both my MAC and Windows computers?
The downloads are specific to either Mac or Windows. You are allowed to install/download the software to any five computers that you own, but if you download to two different operating systems you will need help from customer support.
To call TurboTax customer support
https://ttlc.intuit.com/questions/1899263-what-is-the-turbotax-phone-number
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