Hi atul!

There is no exam named as NEXT. I assume it to be NEET exam , then i would like to inform you that NEEt exam is being conducted by national testing agency (NTA) and this is the first year that NEET exam is conducted by this agency. Earlier , it was conducted by Central board of secondary education(CBSE) .

And this exam is conducted twice an year and in online mode by NTA.

For more details about tjis , follow the given link :

https://medicine.careers360.com/articles/nta-neet

Hope it helps!