Can Nios Board 12 certificate is valid for neet and other goverment exam and It is Good or not and how I fill the form and charge..?

Hey Aayush,
Yes, NIOS board is accepted by all entrance exams like NEET and all colleges for admission as the board is a recognized one. To pursue 12th from the Board is a good option if you want to pursue 12th through distance mode or due to any other issue.
Application forms for NIOS can be filled through Online mode on the official website and make the fee payment either through online mode or through demand draft.
Application forms are available till August First week and afterwards till September you can fill with late fee.
Fee for application form is Rs. 4000/- (without late fee)
For more information regarding NIOS admission, etc., refer this link :
https://school.careers360.com/articles/nios-admission
Good Luck!

Yes, Of course you are eligible to sit for neet and any other government exam. NIOS is an educational board just like CBSE & CISCE. It is run by the Ministry of HRD, Govt. of India. A candidate having NIOS certifications can appear in any national level entrance exam conducted by the Center or CBSE, like JEE (Main & Advanced), CLAT and now NEET. Since NEET is an upgraded or changed version of AIPMT & will be conducted by CBSE on behalf of the Central government of India, there should not be a problem for an NIOS student from becoming eligible to sit in the NEET exam.

Good Luck