What would you do if your parents hit you?

I would tell the police an adult should never think they got right to hit a child.

Hi, I would just like to know what you would do, if you were a young teenager, if your mother raised her hand on you
I don't want to start any conflict, so be nice please

But then wouldn't the teen be taken away?

Avoid being within my mother's striking range, never be alone to with her and always keep an eye out for when her mood is darkening.
Plus save up as much as possible to pay for my own accommodation and plan to move out at 18 without leaving a forwarding address.
That's what I did.

My friend stayed living with her family, has suffered her mother's violent attacks for 24 years and lives with no hope of them ever stopping until her mother is physically incapable to holding a weapon/punching her.

Hi, I would just like to know what you would do, if you were a young teenager, if your mother raised her hand on you
I don't want to start any conflict, so be nice please

Overreact so that I get slapped even more afterwards

But then wouldn't the teen be taken away?

If this has been happening to your friend for 24 year why have you not been a good friend and called the police/social services. it better to protected your friend even if the friendship ends.