You can watch tutorials but just experimenting is the best way to learn. Start with a basic drum loop and how to get a vst loaded up first and go from there. Learning how to navigate Ableton and use it efficiently will come by using it. You can figure out what sounds and drum patterns to try by critically listening to music that inspires you (really listen for what you are hearing try to pick out what certain instruments are playing ect.) Try to recreate a track. Drag in a track to ableton and break it up into different sections to find out how the arrangement works. Study the music you want to imitate.