Welcome to WikiTree, Henry. There's a somewhat complicated process for registering as a member. I think it's designed to ensure that people are serious, but unfortunately it might also discourage serious people like yourself who aren't accustomed to working on websites.
To elevate your status from "Guest" to "Volunteer", go to the page https://www.wikitree.com/wiki/Special:Following and identify one or more surnames or other tags you would like to follow, and state your interest in each one. I expect you will want to follow Douglas and Hunt, and possibly other topics.
After you've done that, you are likely to hear from a Greeter who will confirm you as a Volunteer and provide more information.