What murgatroid said. It's a behavioral-based psychological treatment, related to cognitive behavioral therapy, applied behavior analysis, etc. It's used to treat OCD or specific phobias (which I think they changed in the latest DSM but I'm old and out of school and that's not my field of practice and I'm gross with covid fever so no googling, sorry).

Basically you get exposed to things that cause you mild anxiety and slowly increase until you acclimatize to your biggest anxieties; in recent years research has shown pairing this with beta blockers can be highly effective and faster.