Hello,
First of all Careers360 is a online platform not an university. And if you have done diploma in electrical then you have to take an admission in BTech lateral entry. If you have interest in any other college then you can mention it in the comment section to help you more with details.
And about the marks. You have to score above 80% of total marks to get an admission in any interested college else you have to choose institute on the basis of your secured marks. So it is better to prepare accordingly so that you score a decent mark and take an admission where you feel comfortable.
Hope it helps!