I can't get in to my email account because I had to factory reset my phone, I took a screen shot of my confirmation number. Will the airport except this even though I'm unable to show the actual email from sfo

Stop by the counter and get a new boarding pass from your airline. Many airline's also have kiosks that will enable you to get a new boarding pass without standing in line.

Check with your airline.

Call your airline.

Yes

At the airport you should show a government issued ID. (for international travel this must be a passport) This is the only document by which the airline verifies your identity as a passenger who holds a valid ticket.

Check from your airline

The airline will look up your ticket information, not the airport.