How do I add a password in saved passwords?

Follow the below Instructions:

1. Go to the Settings app on your MacBook
2. Click on Passwords
3. Enter your password or use Touch ID (if available and set up on your device's model)
4. In the bottom, left hand corner press the + button
5. From there you should be able to add a password with the needed information (the website url, password itself & your username/login on the website if applicable)

Also, sometimes, when you login with a website on Safari, you are able to press the "Add Password" popup that may come up as well, which would automatically add the password to your Apple Password Keychain. Hopefully this helps!