What's the scientific consensus on therapies. Are there any evidence that they "work" If so, for what issues, and which therapy to choose? I'm somewhat interes

What's the scientific consensus on therapies. Are there any evidence that they "work" If so, for what issues, and which therapy to choose? I'm somewhat interest in therapies (not for narcissism, but more for issues of self-confidence, anxiety), but I will not spend my time and money without strong scientific evidence.