I’m too scared to talk to my parents.

I'd say talk about it gradually, if you tell them everything in one go it might be a bit overwhelming and hard for them to take everything in.
Instead of going into details you could just say that you've been having a few problems lately and you feel that you'd be better if you had someone to talk to like a professional.
Or if you don't want to talk to your parents first you could arrange an appointment with your GP by yourself and they can sort out further treatment/help that you need. After talking to a professional about how you feel it might be easier to talk to your parents. It's often not as difficult to open up to a stranger compared to a family member.
Hope you're doing okay.

They are your parents, and they love you. Of course they would want to help you in any way they can. Try to find a way to tell them, maybe get help from a friend or someone you can trust to talk to them and get your feelings across. Or write them a letter, it's a good way of getting your thoughts down without fear of being interrupted and letting everything out.
Also, try to keep in mind that it may be hard for them to understand where you're coming from, and it may take some time.

I would start talking to them at the dinner table or while you are in the car with them. This will give you the time and space to sit down and discuss things that you have been feeling. When you do that start small and work your way up. Then one day you and your parents can sit down over pizza and just talk about everything. They will listen to you. They raised you to always be able to come to them when there is something wrong. I bet they would be proud of you as soon as you let everything go. Till then write everything down that is bothering you just so you can remember it all. It also helps you to realize what things are bothering you the most and what are small things that can be worked through on your own. Just breathe and relax. Life is crazy and tumultuous and one day you will realize this.

ask them if you just you and them can have a day together or go out to dinner or even just 20 minutes to talk in a private room. If they don't then maybe reach out to another family member or even a close adult or close neighbor.