Hey
As far as I am aware, Civil Rights in the USA is a new topic specifically for the 2019 HSC (if we want to be more formal, it 'replaced' the old personalities in the 20th Century Syllabus)
The best bet at the moment is to look at the syllabus and build questions around that. Personally, for the key events section, I would have strong knowledge on the event itself, its causes and CRUCIALLY the impact and significance of this event for civil rights? Did it achieve its cause? The Mississippi Freedom Summer, for example, didn't achieve its main goals, however it did have some significant, less tangible effects (freedom schools, preparing for Voting Rights Act 1965, Mississippi Freedom Democratic Party and the Democratic National Convention 1964).
Also, I'm pretty sure for this section they can ask a question from the Survey, so be aware!
Hopefully this does provide some help