You can learn with intellipoker , they teach you very good with videos and you can practice before play with real money and also you can play with coaches who teach you very good all about poker
Just google it. So many articles with specific topics.
If you want videos, youtube and pokerstars school online are just some examples.
But the best is old school which is to read a book. Books tend to give complete info on the topic at hand and somehow telling a whole pic of the story.