Hello,
As you have correctly mentioned, you can apply only for NDA/NA (1) 2020 in the Army wing since you don't have Maths and Physics.
But, you don't have to opportunity to skip the Maths test. It is important for you to score the paper-wise cutoff for Maths paper also.
The other subjects that you will have to study for the GAT Paper are: English, Geography, Physics, Chemistry, History etc.
However, I would strongly advise you to prepare previous papers with timer rather than sticking to book and reading lumps of information. The syllabus is huge, but the paper has repeated models, and hence the advice.
Refer the exam pattern for NDA/NA (I) -2020:
https://competition.careers360.com/articles/nda-exam-pattern
For further guidance and more info about next levels also, you can keep posting more questions on Careers360.
Hope this helps.
Thanks.
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