Always go to the drop off area at SFO. Always, even for pickups.
The app will say if you need to go to the International level or the Domestic level.
The app will also say the door number.
Note: The whole airport is called SFO International Airport, beware if you are reading the pickup spot or the airport name.
Always enter at the farther away Terminal A.
Uber, Lyft, TNC (Transportation Network Company) Lane is clearly marked.
It’s in an island area between the bus pickup area and the non-commercial car pickup area.