MetaMask is itself an extension that supports Ethereum and Ethereum-compatible tokens. It allows its users to create and manage their identities with the help of private keys, a local client wallet, and the hardware wallet. This is because it aims at providing a secure platform to its users.
MetaMask is an extension by which you can access the Ethereum-based apps or decentralized apps in your browser. It helps warns the user in navigating the sites that are suspected to be involved in phishing activities or that have a name matching the popular phishing targets.
You can get back into your account by entering the email address and the password. After completing the login prerequisites, you are ready to go with using the MetaMask extension. Every time you wish to perform activities through MetaMask, you’ll have to log in.

MetaMask Extension | MetaMask Extension