Create a content filter
Go to Service → Content filters
Click on

Click on edit
Enable it and change the name
Click on update
Fill in the items that you want to block and click on update. You need to do this for each sort of items (banned sites, banned url's,…)
Apply a content filter
You can apply a content on one subscriber, a billing plan, per MAC-authenticated subscriber, …
Subscriber
Go to Subscribers → Overview
Select the subscriber and click on update
Select the content filter and click on update
Billing plan
Go to Billing → Billing plan
Click on update a billing plan
Select the content filter and click on update
MAC Subscriber
Location