Welcome! Have you signed up for a blog at wordpress? They have a lot of help documents over there to get you started. The key is to simply have one, decide whether you want your blog searchable by google or not (you can keep it more private this way). Just don’t set it to private because then we can’t view it. You can choose to have comment moderation on but I don’t recommend it. It is harder for other people to reply when there’s a comment hiding that may already say what they would say. It also keeps it easier for you to manage. I’ve had wordpress for many years and not had problems with spam.
For themes you can just pick anything. There are many themes and you can change them whenever you want so I wouldn’t stress on it. Then you’re ready to post away! Start with that much. If you need help setting up the categories (there is a list in the guidance counselor’s office) let me know. But you won’t need it until you finish the intro course anyway.