How is operant conditioning applied in behavior modification?

I could give you the simplest example possible: training an animal (like a dog).

Treats are used to positively reinforce desired behavior, like sitting.

It is theoretically possible to remove a negative stimulus and thereby reinforce the behavior (negative reinforcement).

You could negatively punish a dog by depriving it of a good stimulus, like its cozy dog bed, or by giving it a bad stimulus, like yelling in a dog whisperer-style manner, if it is barking frantically and seemingly for no apparent reason.

Operant conditioning in behavior modification involves reinforcing desired behaviors and using punishments for undesirable behaviors to shape and modify an individual's actions. Positive reinforcement strengthens behavior by providing rewards, while negative reinforcement involves removing aversive stimuli. Positive punishment introduces undesired consequences, and negative punishment removes positive stimuli to reduce unwanted behaviors.