If you forgot you password there are different ways to change it, however there is no option to re-send it or reset directly from login window.
As an advanced user you can ask your colleague (or Admin) with sufficient permission to access your profile in the Object Manager and change your password.
If you have the permission to access the server you can also change it yourself on the Server > Setup > Users Tab.
Web users should ask their manager to change their password in the Object Manager.
As soon as they login to the Web Client they can change it to the preferred one.
RESOURCES WITH WEB ACCESS:
To reset resources password you need to re-send the invitation email.