Welcome CAT from New Hampshire.
"... how this all works."
The "Forum Support and Suggestions" forum on this site has a lot of good information. Learning to use the Search function is also a good idea. If you have a specific question, just start a thread and ask.
Socially, don't hesitate to join into any conversation that interests you. As long as you are polite and avoid politics (a forum rule) , you'll be fine. Most folks here are very courteous and friendly.
Posting your location (at least country or state), gender, and a little about your interests will help you to fit in.