hello aspirant,

officer training academy CDSOTA is conducted in pen and paper mood. syllabus is consist of only english and general awareness. questions are in multiple choice type. totsl 240 questions need to answer, also there is negative marking.  age shold be between 19-25. you can follow below mention books for your preparation.

Combined CDS (OTA) Book   , DDE – Defence Direct Education

Pathfinder CDS   by Arihant Experts

Lets Crack CDS Exam   by SSBCrack