Laura E. Hunter (MVP) said:
Once you've created/modified the security template that you want to use, you
will import it into a Group Policy Object. From the Group Policy Editor
(GPE), go to Computer Configuration, Windows Settings, Security Settings.
Right-click and choosing Import Policy. This process applies all the
settings you configured in the template to all the computers in the
container (e.g., site, domain, OU) that you link the Group Policy to.