Align axis to object normals

I have an object rotated around X axis but its own axis pointing in different directions because it was rotated manually for practicing purposes. How do I align the axis with the normals of the object now considering that I can’t do it manually. Also how do I align the 3D cursor to the normals of the rotated object in case I don’t know the exact rotation angle in order to do it manually in View Panel (N) Another dilemma with the 3D cursor is that even if we rotate the thing it has no effect on snapping or adding new objects raported to its orientation. They are still subjected to Global axis no matter what transformation mode we are in or orientation of 3D cursor.