NDA and CDS have different similitudes however are not one in something very similar. NDA is for the 10+2 level, CDS is for graduation level. NDA test is for national guard institute and CDS is for IMA and OTA. The fundamental contrast is that CDS must be given by graduates. So coming to syllabus NDA has 10+2 level syllabus and CDS has graduation syllabus.
Hope this helps.
All the best!