Hello Abhi,

  I think you are eligible for JEE. As NIOS (National Institute of open schooling) is the board of education under the union government of India. The bronchure says,"NIOS candidates" can appear for JEE Advanced as the qualifying exam from any Public School, Board or University examination in India recognised as equivalent to the 10+2 system by the AIU is accepted". If you are more interested in knowing about the exams which are open for NIOS students then you can visit: https://engineering.careers360.com/articles/engineering-entrance-exams-for-nios-candidates

For appearing JEE exam physics and mathematics is  compulsory .Yes might be eligible for the exam.