This question always bother to students that “Can I Do regular degree and diploma together?”. Here, You will find the complete answer of getting a degree and diploma together.
Firstly, For diploma, you should have completed 10th from a recognized board or from private board and in the same manner for degree, you should have completed 12th or +2 from recognized board or from private board.
If you have completed +2 then their is no need to pursue diploma, go for degree. And if you have not completed +2, then you cannot persue B.Tech and other similar degree program (in this case you need to have diploma).
Now answering you question, you can do both at the same time if you have completed +2. but you have to persue one of the courses as correspondence, Because, You cannot do both courses on regular basis, (Generally, who care about attendence “No one”). If you are planning to persue both courses as regular than it will be difficult for you as you have to miss lectures of one course to attend the lecture for another. So just focus on one.
If you want to do both regular diploma and degree, then you should find a private diploma college which can allow you just give exams (no need of attendence) and join degree as full time course as by preparing for btech exams you can clear diploma exams also.
With the qualification, your knowledge does matter. By following this process you can get two degrees but you can’t get excessive knowledge which is required for job. So choose wisely.