Astral projection and lucid dreaming are the exact same thing. You're journeying to the astral plane the land of spirits good, bad and indifferent that inhabit your dreamscape. There is no difference between the two
Some draw a distinction between astral projection and astral travel, but I think this is a nuance. Astral Projection from meditation is very hard, I do it in dreams, I've heard Mugwort is helpful for this. I've also found melatonin to be very helpful for amazing vivid lucid dreams.