Hypnosis is a state. Hypnotherapy uses that state clinically to produce specific psychological change. Stage hypnosis uses the same state to entertain. When people feel nervous about hypnotherapy, they almost always picture stage hypnosis. The two things aim at entirely different outcomes.
In clinical hypnotherapy, you stay fully aware throughout. You control what you do and do not engage with. The session targets your specific therapeutic goals and nothing else. I start every solution-focused hypnotherapy session at my Edinburgh practice by explaining what hypnosis actually is. Clients who understand the process get better results than those who do not. If uncertainty about what hypnotherapy involves has stopped you from booking, that first conversation tends to resolve it.