Depends on time of day/traffic but I'd say give yourself 45 minutes...
The Presidio is on the north side of the city, so you have to drive through SF to get on the 101. It could take you 20 minutes or it could take an hour, depending on traffic.
About 35-40 min, depending on traffic.
It took us just under an hour around 1pm on a Tuesday using Uber.
The Presidio is right at the Golden Gate Bridge. The Inn is on the Presidio grounds. I have family members living at the Presidio and have made the trip from the airport to the Presidio many times. I usually allow 40 to 60 minutes in high traffic and 30 minutes or so in light traffic.
Get an answer from Inn at the Presidio staff and past guests.