

You have to define ‘we’ and you also have to define ‘WW3’.
Possible scenarios:
-
USA decides to get actively involved in Ukraine’s conflict. Yes, that could spell WW3. Low probability, though, since Trump does not care about Ukraine.
-
Russia decides to attack Western Europe. Probably only a regional conflict, since Trump would probably pull out of NATO. This is the scenario a lot of European nations are gaming today.
-
China attacks Taiwan and/or North Korea attacks South Korea. Probably a regional conflict, but with a high probability of escalation. Trump would drop both South Korea and Taiwan at the drop of a hat.
-
Iran attacks Israel, probably through proxy. Regional conflict. This is already going on, so low risk of escalation.
I would say, like many others, Remmina.
Putty also has a Linux version, so you can use that as well. Its session management is a bit clunky, but it works and it offers some fairly good functionalities.
But ssh is first and foremost a command line tool. As others have said, invest some time to learn its commands and configuration files.