I hate my sister, how do I prevent her and my parents estate from using me or trying to hurt me?

You need to give some detail.  You can't just say "hurt" and expect that we all know what your talking about.  There are many ways that one person can hurt another person.  Some of those ways are even legal.

As an example, your sister might hurt your feelings by saying that all your after is the money.  Your sister has every right to say that and there's nothing you can do to stop it.

No one can " hurt an estate", legally speaking.

Your parents likely have a last will and testament. That describes how their estate will be disbursed. Let your parents know that you don't trust your sister to be the executor of their estate, so please choose a neutral party to do so. This way, dearest sister will have ZERO hands in or any control of their estate /money /assets when your surviving parent passes on.

It is a hard thing to discuss, but ask your parents to be responsible with their final wishes to avoid conflict with your sister after they are gone. A last will and testament isa MUST for anyone with any assets, big or small.

You just avoid them.  

Get an estate attorney as soon as possible.  

If you can afford it, try to get a lawyer.  

How does one get hurt by an estate?  You seem to be confused.  Is English not your first language?

Stay in school because your writing doesn't make any sense.