Don't take these books like "Ars Vercanus" seriously. It contains nothing of value and appears to be written by people who like to LARP around as magicians, with literal 0 occult knowledge and or power because of lack of actual knowledge.
Don't waste your time. The book appears to be a mash of so many things and all made up weird stuff. None of the magical sigils even appear realistic or have tangible meaning.
Be careful what books you look into. Most are useless like this one you mention. But others are also tied in with enemy occult practice and are harmful.