If your hardwired smoke alarm keeps going off, it could be because the backup battery needs replacing. When replacing the battery doesn’t stop your smoke alarm from beeping, try holding the reset button for 15 to 30 seconds or removing dust from the openings in the alarm. If it continues to chirp, it could be faulty and require replacement.

After a house fire, you should not reenter your home unless the fire crew has told you it’s safe to do so. In the longer term, you should not attempt to make repairs to the house on your own. Professional crews are trained to clean up after a fire (including smoke and soot damage), dry out any water damage from the firefighter crews, and make the necessary structural, plumbing, and electrical repairs—and this is all likely covered by insurance.

Baking soda is an effective fire reduction method. However, flour and baking powder are very dangerous around flames. Flour is flammable and it can also conduct electricity. The combination can cause serious injury from electrical shock and worsen the situation by adding fuel to the fire. Baking powder is also not an option as it's also highly flammable. 

You should have either an ABC or K-rated fire extinguisher in the kitchen. ABC fire extinguishers put out wood, trash, paper, plastic, and textile fires along with grease, oil, gas, kerosene, and electrical fires. A class K fire extinguisher is specifically rated for use in the kitchen and is designed to extinguish combustible cooking materials, including grease and fat.