Welcome! As for having a main thing to blog, I started off just posting in one genre (history). I ended up branching out and posting all sorts of things and showing all of my many varied interests, from philosophy, to photography, to politics, short fiction, blogs, etc. It’s actually helped me get in touch with a lot of people in a lot of different communities. On most social media platforms where you develop a following, they tell you to stick to one thing, but I don’t think that’s necessary here!