I want to know about Caste basis and gender basis Reservation offer in Indian engineering service exam

Yes you reservation in Indian engineering service exam is valid for belonging to Scheduled Caste (SC), Scheduled Tribes (ST), Other Backward Classes (OBC) and Females candidates .

Candidates belonging to Scheduled Caste (SC), Scheduled Tribes (ST), Other Backward Classes (OBC) will get age relaxation in required age limit.
They will also get relief in examination fee and final cut off to pass IES exam..

Age limit :
General :: 21-30 years on 1 August of the year of Engineering Services Exam.

The upper age-limit is of 30 years will be relax able upto 35 years in the case of Government servants.

A maximum of 5 years if a candidate belongs to a SC/ST
A maximum of 3 years in the case of candidates belonging to Other Backward Classes
Maximum of 10 years in case of deaf mute and orthopaedically handicapped candidates