Ultimate BlackBerry and Gadget

A friend gave me his blackberry. I am unable to access internet in it, as I can't activate 'enterprise activation', I don't have a password for it. I thought I could connect to the internet through my laptop, I also have a wireless modem. Gan you solve my problem. Thanks.

When i connect my blackberry to my laptop through bluetooth it says i can set up a dial up connection. How does it work and does it cost extra on my cell phone bill?