Hi TreeKangaroo, and welcome to PC!
Your username sorta caught my attention since kangaroos are native to Australia, which is my home country. Although I don't live in the outback, more like in the Sydney city area lol. And I understand if you're feeling shy, most newbies are like that when joining a forum as big as PC but thankfully we have members who can help you out, both staff and non-staff alike. Cirno, who mods this section is always happy to assist newbies like you.
Like what Meganium90 said, why don't you browse around and see what sections grab your attention. I'm sure you'll find something you like, since everyone does eventually. I always feel excited greeting newbies like you since I love getting to know them. I do hope to see you around the forums, and remember if you ever need a new friend I'm always happy to take you on. My VMs are always open so feel free to message me if you want, I won't bite! And as for what that "picture in the corner" is, it's a member's avatar, which you can easily change in the "Edit Avatar" option in your User CP.
Have fun and I do hope to see you around!
- [supporter]Hikari10[/supporter]