Press on the profile icon at the top-right of your screen
Go to your organization page (click on the icon in the top-right corner of your organization page, select the drop-down menu)
Go to the "Settings" tab and then press the "Privacy" tab
Here you'll be able to edit the functionalities of your organization:
When this functionality is active (the slide button is colored), nobody can request to join your organization, only you can invite members to your organization. People can become a member of your organization upon invitation from the admins of your organization.
Hide activity of members
When this is switched on, members of your organization will not be able to see the volunteering activity of other members.
Only members can view who else is a member of your organization when this functionality is switched on (the slide button is colored).
Only admins of your organization can see who is a member of your organization when the setting is switched on (the slide button is colored).