Congrats on taking the first steps! That's a pretty general question that would differ base on your products and goals and there really is no way to offer all the specifics and details here in one post.
Since you have a domain, you now need a WordPress hosting account. Then you choose your premium theme. I have an article that walks you through what to look for in a theme before you make your decision.
Now, you have to read, learn and apply!
First, learn all you can about WordPress and WooCommerce so that you are familiar with both and what each can offer your new enterprise.