Hey!

There are two types of subjects, one is which are taught under training at OTA and second is academic subject. Academicsubjects includes:

military history, military geography, current affairs, service writing, communication skills etc.

And the sujects at OTA training are:

military writing and military law, field engineering, intelligence and security, radio telephony etc.

To get more details, visit here:

https://www.indianarmy.nic.in/Site/FormTemplete/frmTempSimple.aspx?MnId=b+qe2wIZ/mgLL0K6yBvlSA==&ParentID=pnXrj4f81l/w07SDl07q6A==

Thankyou