Learn by doing.
A map of clubs and players all around the world.
It is no secret that I am an OGS guy. So an argument can be made that I am not objective, but to my knowledge it is the only server where you do not have to download anything, supports both live and correspondence games and has a great community happy to help beginners with teaching games and reviews if they ask.
The quickest way to play some 9x9 games (preferrably on your mobile device). No complicated settings, just press play and you will get a game within seconds.
Have fun playing!