Need Advice: Firewall Setup ATT UVerse

Pasadena CA

Description

Need some advice. Looking to set up a firewall to block inappropriate content from the kids. We don't want to use ATT family app, because we want more of an umbrella approach where these sites are not accessible by anyone using our wifi, the same as a library would. What is the best approach? Firewall? Other? Account is ATT U-Verse, business account. ATT has not been helpful after multiple calls for tech support to set up a firewall. Thanks!