Hide sites for non-admins users

Hello,
In my Network, I installed BuddyPress and bbPress in the main domain. But because bbPress automatically set everyone as a bbpress default role (for forums function) in where it is installed (which is the main domain), now the main domain shows in everyone's Admin bar and Dashboard. So if they click My Sites in the Dashboard, they will see 2 sites, 1 is their own sub-site, the other is the main-site which has the main-site dashboard link active. But if they click it, access will be forbidden.

- How to hide all sites in Dashboard/ admin toolbar from a user, if the user is not an admin of those sites?
- Is there a way/plugin can hide admin toolbar for non-admins on one site only (not network)? I tried to use WP Admin UI Customize to hide Admin toolbar from the front-end for selected roles (WP roles) in the main-site. But the role of a new user is a bbpress role which is not included in WP roles, so it does not work at all.

Regards
YZ