When using the Mikrotik hotspot functionality the login page is displayed which is stored on the Mikrotik router. This page is called login.html
and can be modified to your needs.
If you want to use an external site to display to your users you can modify login.html
with http meta refresh to redirect to an external url. You may want to add this URL to the walled garden so it can be accessed.
When the page is displayed, the user is not logged in. A HTTP POST must be done with a username and password to login the user and access other sites. You can do this by adding a form to the external site or the login.html
page to login the user with one click. Without the login any request will be redirected to the login.html
page and/or your external site.