The 'Changing your password' link takes you to IDM, the University's account management system.
This is a key feature for anyone with more than one Google account (eg a personal and a University account).
It allows you to remain logged-in to both accounts, and switch between them quickly.
Once you've done this, you'll be able to move between the accounts by clicking on your picture, and selecting Switch Account from the drop-down menu.
You are advised to use this feature with caution - for example, ensure that you check the account you are using before you send email
You can opt to set up two-step verification, which adds an extra level of security to your account.
You can also review what applications you have granted access to your account (eg a phone app) and view your dashboard etc.