I use Eero Secure on my home network with handful of custom policies (i.e. oldest kid can use discord, youngest cannot) plus Apple's Screen Time for their devices when they're off the home network. It generally works, but also the internet is a deep cesspool and they still find some bad stuff. YouTube is the worst. There is no porn, but loads of other weird and questionable content.

Now that my oldest is 13, I've started to realize that you can only control a portion of this, so sometimes education is better. My setup above works fine for helping my younger two avoid content they might accidentally find. However, every middle school kid can help you kid find a variety of VPN solutions to evade all of this. The latest for my 13 year old was aChrome plug-in that routes that tabs traffic alone over VPN. I unblocked Discord for him in exchange for dumping the VPNs and having a deep conversation over what is appropriate and how to behave on the internet.