To unclog a drain, you can use boiling water, a plunger, or a drain snake. You can also use chemical cleaners, but these should be used as a last resort as they may damage the pipes.
Low water pressure can be caused by a variety of factors such as clogged pipes, corroded pipes, or a weak pump. To fix this problem, you can check the water pressure regulator at the main water line and replace it if needed. Additionally, make sure to check the pipes and replace any that are corroded or clogged.
If you notice a gas odor in your home, it is important to evacuate immediately and call the gas company or an emergency plumber. Gas leaks can be dangerous and should be taken seriously. Do not turn on any light switches or use any electrical appliances until the gas has been isolated and the area is safe.