What can I do to get security updates after the end-of-life for Drupal 7

I have so many websites currently running on drupal 7.

I was just wondering what will happen if I don't move it from Drupal 7 to Drupal 8?

Can I get security updates and bugs fixes after the end-of-line?

How extended vendor support can help me in security updates?

How can we apply security patches to the sites? Is there any other way after that?

Please help we want to keep our sites secure.