For NDA you must be less than 19 and half years of age.
For everything else Bachelor's Degree.

Firstly students shall be citizen of India.
Secondly his age has to be minimum 21 years and maximum 32 years.
Maximum of 4 attempts can be given.

For education qualification, students must be degree holder frim reputed and accredited University either state ir Central or deemed or correspondence.

More details shared below.

https://competition.careers360.com/articles/upsc-civil-services