Are fluorescent bulbs supposed to be changed at the same time in two-bulb lights such as in a kitchen?

Answer 1

No, you only need replace the one that's broken. They all run independently.

Answer 2

It is not necessary to change both fluorescent bulbs at the same time in a two-bulb fixture, but it is recommended to do so if possible for uniform lighting. If one bulb burns out before the other, you can replace it individually. Just make sure to follow the guidelines for the specific type of bulb and fixture.