As you want to appear in UPSC-Engineering Services Exam (Indian Engineering Services) exam and asking fro eligiblty criteria , so I am telling for the same:


Eligibility

Bachelor's degree in Engineering (B.E. / B. Tech) from a recognized university or equivalent. M.Sc degree or its equivalent with Wireless Communications, Electronics, Radio Physics or Radio Engineering as special subjects also acceptable for certain services / posts only.[17]

Age limits

21–30 years on 1 January of the year of Engineering Services Examination.

Upper age limit relaxation is provided to candidates as follows:

A maximum of Three years for OBC candidates [Non Creamy Layer only]

A maximum of Four years in case of Defence Services personnel disabled in
operations during hostilities with any foreign country or in a disturbed area and
released as a consequence thereof

A maximum of five years for candidates belonging to a Scheduled Caste or a
Scheduled Tribe