If you can't remember your Rec Room password you can reset it here: https://rec.net/password/recover
If you're just looking to change your password and know your account credentials, you can change your password by signing in through rec.net and going into your settings, located on your rec.net profile page.
If you are not able to set a new password because you do not have an email attached to the account yet but are still able to log into the account on your device, please see this article on how to attach an email.
If this article did not resolve the issue or answer your question, feel free to submit a ticket with our support staff. Please use the "Technical and General Support" category for this issue.