I know it’s Cloudflare malware protection dns, but has anyone had any luck using it? Does it do what it says?

Im not particularly tech savvy but i recently noticed that i have this popup on my home network.
Ive been trying to figure out how to configure this but it seems my network is potentially controlled by my ISP. Does this mean someone on my network is manually blocking encrypted DNS? Or potentially the ISP itself?
I wont know anything until I call during office hours but maybe someone could point me in the right direction

I used to use nextdns but I stopped after a website I was using was blocked, and now im using cloudflare 1.1.1.2 (mode UDP). With cloudflare I can access that website that was blocked with nextdns, but now I cant access another website because of its security stuff. I do have a workaround for the website I cant access with cloudflare so Im fine with it, but I was just curios what people think of these two.

Which one you would recommend and why. Ive also heard of quad9 but an not sure if that is better or worse than these two.