Generally speaking, there is no policy of changing majors or exemption from exams. After you resume school, you should follow the freshmen of the same major from September of that year. However, the policy of student demobilization is stipulated by the school, and there is no unified regulation by the state. Some schools don't have any policies, while others may. You can consult the armed forces department or the academic affairs office of the school.

Retaining a student's status is only a qualification retention, and it does not mean that you can graduate without completing the required credits. Therefore, it is most impossible for you to follow the original grades in your requirements, because it means that you have no credits from other students during your service, and you can't graduate without credits during your service; The possibility of changing majors is still possible from a technical point of view, because you are resuming freshman courses after resuming school, and there is no problem of credit connection between different majors, just depending on whether your school agrees or not.

Some schools have a preferential policy of halving tuition fees for demobilized college students, and even give them free meritorious service and rewards during their military service. You can find out if your school has such a policy.