Gas Range: Oven and broiler doesn't work, burners do

Help! We have a Kenmore gas range (model number 362.7352593, approx 14 years old), and the oven stopped working suddenly. The stove top burners work, and the oven light comes on when we open the door.

We didn’t move the range, or do any repair…the oven just stopped working!

Is this an easy repair that a homeowner can make themselves?

What part is required?

How long do gas ranges typically last? (do we need to buy a new one?)

thanks!

Pat