Password Protect content() on homepage

You can make the homepage password protected by creating a page and selecting it in the admin Settings > Reading > Homepage Displays. Then on the page settings make it password protected.

Then create a template called front-page.php and use conditionals to show/hide the content.

For Example…

if ( ! post_password_required( $post ) ) {
    // Password Protected Content
}else{
    // Password Form
    echo get_the_password_form();
}

More info on password protected pages.

Note: If you have already entered your password, you can delete your cookies and refresh the page to see the password form again.