Group chat & social media during NC

I’ve just started No Contact (my ex broke up with me about a week ago, but we met to talk it over one last time three days ago, and I’ve been doing NC since then), and my ex’s and my closest friends are mutual. We have a group chat all together, and I was just wondering what the rules would be on that? I don’t want to totally neglect those friends/that group. Should I not post in there at all? Should I only reply to others? What’s the best way to go about that?

Also, what are the rules for social media if we still follow each other? Should I avoid posting until the end of NC?