1) Toolbar Removal 2) Test Env't /backup questions

Two questions:
1) My site uses a custom theme and it appears I am unable to prevent my users from seeing the black WP toolbar at top of page and accessing the WP dashboard. The dashboard page clashes with the style of my site and I don’t see a way to customize this page. I believe my site can handle all functions (login, profile admin, etc) without my site visitors needing to access this toolbar. Does this toolbar serve some necessary function or can I get rid of this option for my site visitors?

2) My site is not technically sophisticated but nevertheless I prefer to preview any site changes I may be considering before implementing them in production. Is there a quick and easy recommended method of setting up some sort of test/mirror environment in WP to handle this process? Also, if there is a failure of some kind and I need to rollback to a previous version of the site, what is the recommended
way of setting this up (considering the fact that the admin does not have a strong background in WP).

Thx.