I have a debate ,the topic about euthunasia or helping suicide,and I have to convince the audience that I am with this type of killing

I would watch the Movie "You don't know Jack". Also Google:
Jack Kervorkian.

First, define your terms. Assisted suicide is not the same as euthanasia. The difference is who initiates the homicide. In suicide the person initiates the killing themselves. Euthanasia is initiated by another person.

You have a very challenging task ahead of you. Above I used the term "homicide" correctly but most people will not think so.

Check Pro-Choice websites, many of their arguments are well written. Pro Death Penalty arguments should also be researched.

Good luck.