how can i word this differently:

People advise others to stay clear of the horrible consequences of despair.

You have two non-specific words -- people and others. What are more specific words you can use in their places?

Do I have to make them specific if that is my top sentence for a paragraph that relates back to this thesis: The characters of the novel demonstrate how misery drives people to do things they would not normally do.

Yes, I think you do have to use a specific word for people. Who advises others to avoid despair? Who advises other characters not to lose hope?

Okay. Thank you for your help.

You're welcome.

How can I rephrase the sentence: "People advise others to stay clear of the horrible consequences of despair"?

One possible rephrasing could be:

"People commonly offer guidance to others, cautioning them against the devastating outcomes that can result from succumbing to despair."