securly.com é seguro?

An annoying extension used by schools on Chromebooks to restrict access to the internet. However, its regular filter blocks useful sites like Reddit, Spotify, and many other music sites while not blocking literal games. Although many think I'm saying this because I want to go to social media sites and such on my school Chromebook, I don't; I just want a device at school that can access more than Google sites and a few others.

I swear I was just browsing along when all of the sudden, this site took over half my connections, all i get is a error message saying my ip is not registered but unusual, why am i being sent to this site? I set up no proxies, was it a recent program, installation? Should I format my computers? all other PCs on my network are fine, and i swear i set up no proxies. so confusing, I'm blaming the site.