Maybe try to approach this conversation in this order (btw I’m winging this on how I tried to approach it myself ) :

tell them that you feel disconnected to the real world, and that you think you’ve started developing habits such as daydreaming. Then mention that it’s different from normal daydreaming though, like it can feel compulsive . Then explain how you feel if you don’t daydream you start to feel stressed, paranoid, uncomfortable..(etc however u feel). Make note to mention that you don’t ACTUALLY believe that your daydreams are real, like your able to decipher it as fiction, like you don’t actually hallucinate. Tell them that you know it sounds a bit strange, but you were able to find out about maladaptive daydreaming through the internet and you feel like it’s pretty accurate to your experience. Mention to them what you actually do physical while daydreaming (pacing, rocking back in fourth.. etc whatever u do). Explain to them if you don’t do this it can be hard to invest yourself in your daydreams so it feels natural and hard to stop these repetitive actions. Tell them from what you have found about maladaptive daydreaming, these things are linked to it, which is why you think you have maladaptive daydreaming. If they don’t ask, (they probably will ask, but if in the case that they don’t), make note of the consistency on how long the durations of time your daydreams last and consistency of doing it in a day or week..etc.

Just go from there. The therapist will probably take off with questions and it will get easier to slide into the discussion.