Martin Luther King said it well when he remarked,
“Our lives begin to end the day we become silent about things that matter.”
― Martin Luther King Jr., I Have a Dream: Writings and Speeches That Changed the World
You don't have to know it all, and you don't have to be eloquent, but you should be respectful, open minded, and thoughtful when you speak up, and you should know what's most important about your words.
Many stay silent and that's a problem--we need to speak up when we see injustice, have a solution to a problem, and can help. MLK was right.