I personally feel that you should utilise your MBBS first year to build your concepts in Anatomy, Physiology and Biochemistry rather than thinking too much about NEET-PG.
Due to tougher competition and less seats in PG,medical students start taking tension about PG as soon as they enter medical colleges.The result is that they neglect their practicals or clinics,devoting more time in theory and/or solving MCQs.
So it should be avoided in the first year.