Calm under pressure isn’t a personality type. It’s reps of staying steady when it counted less.

Composure looks innate and is mostly accumulated. People who are steady in big moments have usually been through dozens of medium ones and practiced holding their breathing and their attention there. Nothing special happens on the big day, they simply do again what they have done before. The training happens when the stakes are low enough that failing costs nothing.

Use ordinary situations as practice, a question in class, a conversation you would rather avoid, the last rep of a set. Do the same steadying thing every time so it becomes automatic.