How do I find all my passwords

The key one is the one to your Apple ID. This Apple article has instructions for what to do if you have forgotten your password --> If you forgot your Apple ID password - Apple Support

or go directly to this link --> http://iforgot.apple.com/

If you still need help:

Contact Apple for help with Apple ID account security "This article provides country-specific Apple Support contact information for customers seeking help with their Apple ID password or other security-related issues." --> Contact Apple for help with Apple ID account security - Apple Support

If you find you can’t sign in, reset your password, or receive verification codes, you can request account recovery ( How to use account recovery when you can’t reset your Apple ID password - Apple Support ) to regain access to your account. Account recovery might take a few days or longer, depending on the specific account information you can provide to verify your identity.

Once you're into your iPhone, read this support article How to find saved passwords and passkeys on your iPhone - Apple Support