If you use the keyboard shortcut Ctrl+Shift+L, you can just repeatedly press the key combination to cycle through each login.
Alternatively, just open the Bitwarden browser extension (by clicking the Bitwarden icon at the top of your browser, or by using the Ctrl+Shift+Y keyboard shortcut), which will chow a list of all available logins; then click on the login that you want, which will auto-fill it.