Unzip it?  What did you download?   You need the data file ending in .tax2017 and the 2017 Desktop program to open it.  But it is too late to amend 2017 and Turbo Tax doesn't have the 2017 program anymore.

You may have misunderstood.   You cannot get any additional refund by amending a 2017 return now, since it is more than three years past the original filing deadline for the 2017 return.   It goes by the filing deadline for the 2017 tax year, not by the fact that you filed two years after the deadline.   What are you trying to change?

@glassrestoration - the deadline for getting a refund from the 2017 tax year was April 15, 2021....so you are past the deadline. 

However, if your reason for submitting an amendment is you believe you owe more tax, then you'll have to amend.