In a typical residential electrical setup, a circuit breaker serves as a safety device that automatically trips and shuts off power to the circuit when it detects an overload or short circuit. When you are using multiple appliances on one breaker/outlet at once, the total power draw from those appliances adds up. If the combined power draw exceeds the circuit's rated capacity (usually measured in amps), the breaker will trip to prevent overheating and potential fire hazards.
When one of the appliances is turned off, the power draw from that specific appliance is eliminated, which may bring the total power draw below the circuit's rated capacity. In this case, you might not need to manually reset the breaker; it should automatically reset itself after a short pause (a few seconds to a minute).
However, if the remaining appliances still draw enough power to exceed the circuit's capacity even after turning one off, the breaker will likely trip again. In this situation, you should reduce the load on the circuit by unplugging or turning off additional appliances until the power draw is within the circuit's limits.
It's important to remember that constantly tripping a circuit breaker due to overloading can lead to wear and tear on the breaker and may indicate that you need to redistribute the electrical load in your home. If you frequently encounter tripped breakers, consider having an electrician assess your electrical system to ensure it is safely handling the load.