Thanks, that helps. When you post a question, then please give us as much information as possible so we don't need to go through several posts to help you. And it prevents misunderstandings.
You would need to either use a smaller needle or less stitches. A hat needs to measure about an inch or two less than the head measurement. They stretch a lot and if you make a hat the same size as the head, it'll be too big. Here's a basic hat pattern
that works with any yarn, any needle size as it uses the stitches per inch you get with your yarn and needle.