I think I understand where the confusion comes from. On the primary side, the transformer coil is a load. Therefore, electrons flow from negative to positive. On the secondary side, the transformer coil is a generator, therefore, electrons do NOT flow THROUGH the coil from the negative to the positive, but from FROM the negative THROUGH the circuit TO the positive side. Hence the confusion I am sorry to say that I got more answers mocking me for not being a "conventional current supporter" and sticking to academic prayers, rather than explaining to me how both conventional current and electron-flow point of views relate. Thanks to all constructive comments though.

I think I understand where the confusion comes from. On the primary side, the transformer coil is a load. Therefore, electrons flow from negative to positive. On the secondary side, the transformer coil is a generator, therefore, electrons do NOT flow THROUGH the coil from the negative to the positive, but from FROM the negative THROUGH the circuit TO the positive side. Hence the confusion Thanks to all constructive comments though.