What should I do? Plz help

So one of my guy friends likes me and I told him that I like him too bc I thought I did. He asked me out and we’re going to watch some movies at his house on Saturday. I now realize that I might just like him as a friend. I honestly don’t want him to hate or dislike me but I can’t lie to myself or him. It wouldn’t be fair. My really good friend is also his best friend so idk what to do to make sure she’s not made at me either. I can’t lie to myself or to him. That’s just not how I want to start a relationship. Plus, I really like someone else. Plz help. What do I do??