>>cubefo+oz
You don't need to do all of this, just install a pihole on your network and block all social media sites. Then literally every device on your network will block them all. No need to faff around with other apps, etc.
If you want go to even further, use a hosts file to send all these sites to localhost and set up an ad blocker to block the html tag on all these sites as well. Now you've blocked the sites 3 different ways.