1. Go to "Block Members" Settings Page :
Check this topic on How to access buddypress block members settings ?
2. Set What Roles Can Block other Users and what roles cannot be blocked ?
Check this topic on How to set what roles can block members and roles that cannot be block ?
3. Set What Restrictions Will be Applied on Blocked Members and What Restrictions Will be applied on Blocking Users.
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4. You can Manage all Block Operations from the admin block members table.
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