According to CDS eligibility criteria 2020 , candidates applying for the exam must be 20 to 24 years. Candidates who have passed graduation or appearing for their final year are eligible to apply for CDS exam provided they submit a relevant certificate of passing the examination at the time of commencement of course.
So , Yes,You are Eligible! as your Age is 23 years old currently .
Best of Luck For the Exam!