What is the purpose of this essay? TOELF? IELTS? It's good to know why you wrote this to base our comments on more task specific requirements :D
Any way, let's have a look at your introduction;
Many people believe that people must obey their authority's decision. However I believe that people should protect rights and stand up against authority's wrong decision because sometimes it leads people to disaster.
This is not bad, but you should have introduced the topic in more details. It is always good if you have a hook statement, which is the opening sentence that comes with a punch to grab the reader's attention. Here you do not have a hook. It can something like;
Authorities reserve the power of decision making to themselves. ... remember, your hook should not only be interesting, it should be relevant to your topic too :)