To truly learn how to control your emotions, you first need to understand the basics of psychophysiology and conditioned reflex, then master the techniques of self-hypnosis and learn self-regulation
I myself am now deeply studying this issue. I can recommend a good book that will give the right direction of thought on this topic. Book: Anthony Robbins "Wake up the giant in you." I want to warn you, you can't learn this in one day. Our emotions are the same "muscles", in a figurative sense, which need to be constantly pumped and kept in good shape. And, of course, if we don’t give up, our work will bear great fruit and you will learn how to manage emotions.
Learn first-class self-deception and suggestion. If you strongly believe that the fire does not burn, then you can calmly smile in a burning room for 20 seconds