is Maharastra CET exam necessary to join the Indian Army?
I think you are highly mistaken. You can never ever Qualify MHT CET to end up in Indian Army. Of course there is an Institute named as Army Institute of Technology in Pune, which accepts MHT CET Score and only wards of Army Personnel are allowed admission. For more information about MHT CET do follow the link below
https://engineering.careers360.com/articles/mht-cet
Whereas for Indian Army, you have many ways of Joining a Cadre, with the first one being NDA followed by SSB Exam and Interview. You even have Engineering and Medical Corps in the Indian Army, and they have Annual recruitment Tests followed by SSB Interview.
To know more about how to join the Indian Army do follow the link below
https://competition.careers360.com/articles/How-to-join-the-Indian-Army/amp