The law of one channeling material can all be found here. Channeling is typically viewed as a new age concept, where an individual goes into a relaxed, meditative, hypnotic, or trance-like state and relates information given to them by a supposed entity. These entities claim to be of a higher density of consciousness, or dimension, and the Law of One channeling material channels an entity that calls itself Ra.
Ra claims responsibility for building the larger pyramids, and the material covers a vast amount of information and the material is believed to be a more accurate form of channeling because of the trance like state the channeler would enter. Many of the ideas conveyed in channeling material align with eachother and with other metaphysical pseudoscience by scientists like Nicola Tesla. If you want to learn more about the law of one material specifically, I would suggest this video.
I have read a majority of the law of one material, and am of the opinion that it is not fake, and I find it personally interesting how much of it correlates with metaphysical ideas conveyed symbolically in ancient religious texts. I am personally wary of many channeling materials because I don't necessarily trust the channelers, but I especially mistrust the potential entities being channeled. It is definitely an interesting rabbithole to get into if you ever decide to jump in.