Is there any classified form of stratigraphy in which we can see which beds or formations are marine which are fresh water. please tell me the main main points.

Well i don't think that there exist any specific study related to the formations and the environment related. You have to cram alot, as stratigraphy in rare cases involves concepts...

NO YOU HAVE TO GO THROUGH BOOK AND MEMORISE ...YES IN HIGHER STUDIES YOU WILL KNOW ABOUT TECTONICS SO THAT YOU CAN EASILY KNOW TGE BASIN AND ALL...FOR EXAMPLE SHALE IS A MARINE SED...