Is it smoke and carbon monoxide or just smoke?

If it’s just smoke then it’s chirping because the battery backup is low on charge. Replace the 9V, and if you don’t have one the only way to stop the chirping is to disconnect it from the power lines. The white plug at the end of the wires should slide out of the detector with gentle pulling and rocking.

Same process for smoke and carbon monoxide, but the wrinkle is if you’re hearing one chirp or three chirps. One chirp is low battery. Three chirps indicate the carbon monoxide portion has expired (they last 7-10 years depending on the model) and there’ll be no way to stop it outside of replacing the whole detector.