A couple of membership questions; On my site, when someone

Hi

A couple of membership questions;

On my site, when someone clicks on any of the sign up buttons at Link removed at members request they just get redirected to the home page. Why is this please? I've obviously missed something vitally important, just not sure what?

Also;

In Membership > All members, no new users seem to get automatically given an access level. Should they?

Thanks