An option so users only log in to the site, that they own

Hello guys,

When new users creates a site, they are automatically logged into my main domain (forenigo.dk). Can I restrict this, so that they only can log into the site, they just created (examble.forenigo.dk)

I know they can't do anything else than change profile info in the backend of my site, but it could be nice if they are only allowed on their own site.

Thought it has something to do with the settings here:

So theres maybe two things in this:
1. Do not allow users to be automatically signed in when creating an account/site
2. Restrict the users to their site only

Thank you.

Best regards
Nicolaj