Norton Safe Web uses Norton Accounts to manage user accounts. When you signed up for an account on Norton Safe Web, a Norton Account was created for you. If you need to change your password, then login to your Norton Account and select "Change Password".
A very useful program and Norton doesn't have issues with it. However, i ran Windows Defender and it detected adware, namely Opencandy. As it's a free program, i suppose it's to be expected. Nothing serious but something to watch out for.
Thanks for joining the Norton Safe Web community. Since this is your first time signing in, please provide a display name for yourself. This is the name that will be associated with your reviews. It will be viewable by everyone. You will not be able to change it later.