Congratulations on your new iPad! You may need to deactivate your friend's account before you can setup your own. You may need your friend to log in one last time to help with the deactivation process. I found an article with the steps you need to do this:
To completely disassociate your Verizon account from your iPad Wi-Fi + 3G, follow these steps:
- Tap Settings > Cellular Data > View Account.
- An account login screen will appear. Log in with your username and password.
- The Account Overview screen appears. Select Add Data or Change Plan.
- The Add Data or Change Plan screen appears. Select Cancel Plan.
- The following options appear:
- Delete Account Now: Select this option if you want to remove this device from the account now.
- Delete Account Later: Select this option if you want to discontinue the monthly service for the next month only; your account information will remain with Verizon.
- You will receive a confirmation that the plan was canceled successfully. To finish resetting the account, proceed to the next step.
- Tap Settings > General > Reset: Subscriber Services.
- Tap Reset Account.
- Your iPad will prompt you to confirm the account reset. Tap Reset to complete deactivation.
You can find the full article here:
I hope this helps you get started with your new iPad!