No, you don't have a right to free speech on Facebook. No, the government can't ban bookshops from selling books about $Topic. One of these would be the governm

No, you don't have a right to free speech on Facebook. No, the government can't ban bookshops from selling books about $Topic. One of these would be the government suppressing free speech (the bookstore's free speech, not their customers'), the other does not involve the government at all.