FortressOne

FortressOne is a free, community developed, open source, fork of the original 1996 QuakeWorld mod Team Fortress. It is a fast-paced, class based, arena first person shooter remastered with refined graphics, new mechanics and evolved gameplay.

There are still active communities that play the original teamfortress everyday,
-Oceania
-North America
-Europe
-Brasil

If you are interested in playing, please check out the website and join discord. There are plenty of people to help you get into the game 

-FortressOne Team 

www.fortressone.org
www.discord.fortressone.org