What Is the Basis of the System of Dwita Vedanta?

Shankara chara, the commentator the interpretation we shall follow, gives his commentaries. They are called bash he commences on ten of the opanishots. His commentaries are the basis for adwita vedante and will come to the term a dwite. Then there you have the smithy prastal weknow, the non vedic literature which supports and base based on wales are called smithies. And that's how we understand these three. Same upanishos, same gita, same brahma sutra, but multiple commentaries with different interpretations.