Not true. The science classes for nursing do not fulfill the prereqs for med school. They are easier, and more superficial than the prereq classes for med school, plus the prereqs for med school do not include anatomy, physiology, or microbiology (one takes these classes in med school). Nursing students do not take the same year of inorganic chem and year of organic chem, year of biology, and year of calc based physics, all with labs. None of the classes are the same. The tracks are totally separate, not interchangeable. If a nursing grad decides to go to med school, they will have to do a postbac, premed course. If a person with a BA/BS in science decides to go into nursing, they would have to take a BS to BSN course.
It’s not that one cannot switch streams, but at this point, for this student, it’s really a choice between do they want to go to nursing school or to an academic, arts and sciences bachelor’s program, while also doing their premed requirements, and try for med school (or PA).