Please enter the first part of your address in this way, replacing the numbers with your own:
Street Address: Mile999 Site9
PO Box: PO 9
RR: RR 99
The city, province & Postal Code should be filled in as normal.
If you have TurboTax Live Assist & Review, here is how to talk to a Tax Expert: https://turbotax.community.intuit.ca/replies/3456106