I just want to ask intelligence has 75 soldiers, how do I suppose to get all those 75 soldier, and is there a book which explains those 75 soldiers?

by

Yes those 75 are discussed in the first chapter of Usul Kafi. We discuss them here in this class:

https://youtube.com/playlist?list=PLrK-FXb0E44utlqTeafpwSWjyT_xncI19