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.
Melatonin can be very harmful when you take too much of it or take it too often. I have sleep issues and many health problems came from taking too much melatonin.
Lucid dreaming, unlike astral projection, is a scientifically proven psychological phenomenon that involves controlling your own dreams. It is not leaving the body or sending something out, it is all happening within your own subconscious mind; in other words, lucid dreaming does not affect the subconscious mind of others, only your own.While there have been studies about astral projection, there was nothing entirely conclusive about the existence of an "astral body" or anything of the sorts.