Am I eligible to apply for the NDA after 12th (Commerce) without Maths????

Yes you are eligible to apply for the NDA after 12th (Commerce) without Maths But you can join to Indian army only.

Here I am giving you the details of NDA examination:

A candidate must be either be a
a citizen of India , or
a subject of Bhutan, or
a subject of Nepal, or
a Tibetan refugee who came ovbet ot India before the 01 January , 1962 with the intention of spermanently settling in India, or
a Person of Indian origin who has migrated from Pakisthan, Burma, Sri Lanka and East African countires of Kenya, Uganda, the United Republic of Tanzania, Zambia, Malawim Zaire and Ethiopia or Vietnam with the intention of permanently setting in India.

Sex:
Only unmarried male candidates are eligible.

Required qualification:
For Army wing of National Defence Academy:
the applicant should be 12th Class pass of the 10+2 pattern of School Education or equivalent examination conducted by a State Education Board or a University.

Physical requirements: