What is Kagurabachi even about

I read the first 20 chapters of this manga and I cannot understand what is happening, i get his dad made swords and he trying to destroy it but who is the girl, why are people are attacking him, who is the organisation Azami is in thats helping him Chihiro, who is Shiba, who is the Elite 4 type group with glasses, girl and mask guy, what is the war, what happned to his dad EDIT: I get it now, I reread it and it makes sense now