Loosing a password is unpleasant situation where you have a option to create new account but in this case you can reset your old password by following these steps:
Open the login page of Blooket.
One the login page click on the forget password button.
Follow the steps to prove the authenticity of your account.
Finally create a new password.
Read the gude for more detailed steps to forget Blooket password: https://ityug247.com/blooket-login/