No. Passpack only stores your passwords, it will not change them on other websites.
If you would like to change your password on a website - for example, Gmail.com, here's what you should do.
- Open two browser windows or tabs: one for Passpack.com, one for Gmail.com
- Login to your Gmail account as you normally would.
- Navigate to the change password option (for gmail, instructions here).
- In your Passpack account, locate your Gmail Entry and open it.
- Click Suggest password to have Passpack suggest a new password for you.
- Copy it.
- Press OK in your entry and save it.
- Go back to the Gmail password change page, and paste in your new password.
- Complete the Gmail password change process.
If you make a mistake, and need to know what the old password was, here's a trick that you can use.