The Essential primordial beej mantra is “om”, it's the mantra from which all one other mantras have been born. Every single beej mantra has a specific god or goddess linked to them. The kinds of beej mantras are— Yog beej mantra, Tejo beej mantra, Shanti beej mantra, and Raksha beej https://www.youtube.com/watch?v=7yoEpl90KUg