How can I use the chat box?
In the top right corner of the Chatbox, click Log in. You'll automatically log if you're already logged into your account before, else you log into your account then.
How can I change my password?
After you've logged in, click Profile at the top, under the banner. From there, on the third line in your Information (where you are automatically taken), it says Change your password: . Then click Modify, which is straight across from it. From there, you just enter your old and new passwords and hit Save.