you could open the terminal and type ping -c 1 lemmy.ml which will send an echo request to lemmy and see if it replies, and will also tell you what IP address your computer is currently resolving the name to. if it is an IP address other than 51.38.185.90 then you are dealing with DNS censorship which is usually easy to circumvent by using a different DNS server. if it has the correct IP and some error message or a timeout, that would be interesting.

if you want to paste the output of that command here, to copy text from the terminal to your clipboard you can use ctrl-shift-c (instead of ctrl-c like in other programs, because in the terminal ctrl-c by itself sends an interrupt signal to the running program).