You can’t perceive reality undistorted by your emotions. Understanding yourself, how you feel, and how this filter affects your lens of the world, is important for your success and happiness.
Look back to your beliefs, events, interpretations and fears to control your emotions. If you can’t control your feelings, you can’t control much else.
I think “understanding” your emotions and dealing with them appropriately may be a better term than “controlling” your emotions. We should recognize what we feel. Many emotions are positive and provide us with much joy and pleasure. It is the negative ones that can be troublesome when allowed to run rampant and give us difficulty. Admitting you have an anger problem, extraordinary anxiety, or other difficulty is the first step in learning how to manage it so it doesn’t interfere with your success and happiness in life.