Blocked IP addresses (including app stores?)

For the past week or so, the majority* of the phones at my house have had issues with different website and connecting to them. This includes websites such as https://oldschool.runescape.com/, apps such as Splitwise and Venmo, and even the App Store for Apple. This is across multiple iPhones and a Pixel 4. We literally can't even download apps on Wi-Fi. Has anyone encountered this before and found a resolution?

* one person hasn't had issues with her personal phone but on a test phone she can't connect to things either.