Hello,

I hope you are doing well, Sorry but to apply for CDS you must complete your graduation first with 12th having Maths and Physics. Diploma is something that is considered as equivalent to 10th. So After Diploma you must complete some Graduation Degree like Simple Graduation with Hons paper or B-Tech. But with diploma you can apply for NDA(National Defense Academy).

I hope you find this information helpful. I wish you all the best for your future.

Good Luck