NIOS 12th

Yes, as per the eligible criteria of JEE Mains 2019
for qualifying exam, there is an option
*National Institute of Open Schooling conducted Senior Secondary School Examination with a minimum of 5 subjects.*
The 5 subjects for B.Tech/ B.E. are:
1-Language, 2-Physics, 3-Mathematics, 4-Any one of (Chemistry, Biology, Biotechnology, Technical Vocational Subject), 5-Any other subject
Best of luck.

Hi, NIOS certificates are legally valid in all institutes and universities in India. As it is a board under central government like CBSE and CISCE etc. Further the minimum eligibility criteria for BHM from Amity University, Lucknow is 12th passed only. Hence you are eligible.

Yes, NIOS board is applicable for admission in IIT or NIT.

NIOS is regarded to be valid at par with any education board for class 10th and class 12th in India, as per GOI and Council of Universities or others in India.

Thing is, you must get the result before the cutoff date of result govern in notification. No one is concerned with which month you appeared. Eg, if cutoff date was 31st July 2018, then in your case you will be fresh applicant in 2019 and 1 year drop in 2020. In such case for that particular entrance, you can't take admission via that NIOS result of August 2018 in year 2018.

NIOS is equally valid like any other board. Only requirement is most admission need you to clear the subjects in same sitting.

JAM is for Masters, and NIOS is a board for class 10th and class 12th. There is no link between them. JAM board is more concerned with your eligibility test and your qualified degree.

NIOS is equally valid like any other boards, as per the GOI and other University boards or councils.

Yes, you can. Candidates need to have passed 12th board examination of 10+2 schools system and should have secured a minimum of 50% marks in aggregate of the subjects in the qualifying examination.