This greatly depends on the species of plant and how hot the fire was. Evergreen trees rarely resprout, but many hardwood trees and shrubs do. Some forbs and grasses also resprout from underground bulbs and roots or from the root crown if the fire wasn't too severe. Also, many native plants — and especially invasive species — reseed burned areas with light, wind-borne seed.
To see if the plant in question is still alive, scrape off a little of the bark near the base of the main stem. If the underlying cambium is white and moist, the plant is alive; brown and dry means the cambium is dead. Most resprouting is from the roots, so a "wait and see" approach may be the best answer.
