You are not supposed to be afraid of your parents
You never deserve to be hit (not even lightly, not even if you killed someone)
No one has the right to touch you without permission, not even your family members, including your parents
Your parents can love you and still hurt you, that does not make the hurt okay
Adults you trust can still be wrong
It's not normal for everything to always be overwhelming
If you are having a problem with any of these things, do your best to talk to a licensed therapist (if they are licensed therapists they legally cannot tell your parents your personal information)
You are not alone in your struggles
Your struggles are valid, no matter how small they are
You deserve love and kindness
You deserve to be surrounded by people who love you and care for you
Edit: lots of people are commenting saying that therapists can and do tell parents information about what their child says in therapy, the legality of this depends on your age and what type of information it is. Here is what the American Psychological Association says about it
Discussing confidentially with your therapist beforehand is a good idea so you know how your specific therapist feels, but it's horrible that that's something you have to do. You still deserve privacy as a child.
If you are in a situation where you can't tell your therapist something, please get the information out of yourself somehow. I recommend saying it out loud if you can even if it's just to yourself.
Failing that, write whatever it is down and get rid of the paper so it's unreadable if you have to, it's better than keeping everything inside.