Burner on stove won’t light

It really depends on the model and why it’s not working. If it is a gas stove, as it sounds like, is the igniter even activating? Do you hear it clicking? If so, then it could be a gas valve issue. If not, then the igniter needs to be cleaned really well. As debris or grease/carbon buildup will prevent the electrode from making contact to offer a spark to ignite the gas. Many times a burner doesn’t light due to this. I usually clean with some rubbing alcohol then use a small piece of sandpaper to clean off the exposed metal part on the igniter itself.