The park is open year round. Plan to spend a few days. There is a lot to see. I spoke with a couple from South Carolina who allowed 1 day and were very disappointed to miss so much.
Take the drive and visit the different battlefield.
The roads are open year round, the main visitor center opens & closes at regular times, and they might change slightly based on the season, but itll still be open at least 8hrs a day, google the park website to check the specific open times.
I don't think it closes.
Visit this page, it has everything about seasonal hours and what is open: nps.gov/gett/planyourvisit/hours.htm
Thanks! Your answer is awaiting moderation.