Can I upgrade to first class at Alaska Air?

Passengers, You can upgrade a seat on Alaska Air by purchasing an upgrade or using miles or elite status for a complimentary upgrade. but availability depends on seat availability and your fare type. to make Alaska Airlines upgrade to business class or first class-

Use Alaska Mileage Plan miles to upgrade eligible fares.
Purchase an upgrade during booking, check-in, or at the airport.
Elite members can share upgrade codes with friends or family.

For more info Alaska Air upgrade to first class, visit the airlines official website or call them and read blog at the link-

https://www.airlinesgrouptravel.com/blog/how-to-upgrade-on-alaska-airlines