Every account you told your browser to "save password" for is stored in the browser's password manager. When you move to a new phone or computer, need to type a password into an app by hand, or want to move your passwords to another password manager, you can view these entries and export them to a file.
This guide is only for passwords on your own device and in your own account. You may be asked for your device's screen lock or your account password before passwords are shown. The exported file is not encrypted; you need to delete it when you are done, and we explain how below.