When you are logging in to the TargetEveryone platform for the first time you go to https://www.targeteveryone.com.
Click on the blue log in button in the top right corner.
Then you type in your username and password. Your username is the same as the email you have registered. If you dont remember your password click on "Forgot Password". Then you will receive an email where you can reset your password. If you want to change your password go to the article Change your password.