Diploma

First of all, this is not possible as you can't pursue two courses at the same time and it makes no sense to pursue Diploma and degree course together.

Hi Vaishnavi,
Please mention the name of the diploma you want to pursue, as eligibility will vary accordingly and you may not be qualified to go for each one of them.

You can appear for NDA after completing class 12th. You can join army through IMA and OTA after completing UG.

It's better to clear your 2nd PUC. For pursuing Diploma course, the minimum qualification required is class 10th, but to pursue B.Sc, the minimum requirement is class 12th.

You can try for engineering in Canada. Top Canadian universities offer great prospects for engineering graduates and also a world class education. However, most of the universities do not understand Diploma and require a grade equivalent to class 12th. You can get your scores evaluated from some standardized evaluation company and look out for the application requirements at the university websites.

7.30 CGPA is quite good and you can look for admission in universities like Adamas University-West Bengal, Lovely Professional University-Jalandhar and DPU-Delhi.