The best course that I would recommend for blogging would Communications & Technology. Any courses dealing with technology, media and or communications will naturally set you up for creating and running a blog. Organizational Communication can assist you in making the blog a business. I wish you the best on your journey.
Blogging is now becoming a great platform for people to share their ideas/stories or to grow one's business.
Before starting a blog, ask yourself the niche in which you would want to start the blog so you can create the content accordingly.
You can go through https://www.shoutmeloud.com/ started by Harsh Agarwal who also started blogging couple of years back. This site has grown over the years and offers great insights into blogging, tools and techniques. They also offer free courses on blogging.
Enjoy learning and All the very best!