The Pull—off and hammer on are a vital bass tequnique, mainly used, I think,
with slap and Pop.
To practice one, play a note on a fret with your left index finger on the fret,
then put on your third to a fret higher up (it doesn't matter which fret).
Pull your third finger off after a moment, and as you do, pull the string with
it away from you.
It is very easy to learn
Have confidence, Al