Hello Manish

Cutoffs of colleges under DU are reaching new heights year after year. I don't think that you'll be able to secure  a seat in any of the most common branches in BSc in DU, but you can definitely try. Cutoff of zoology, botany hons are quite low as compared to other subjects, they might drop to your percentage in 2nd or 3rd lists, so don't lose hope. Moreover, you can apply in various private universities in Delhi NCR like Amity University, etc.

If you're interested in any other course other than BSc then you may apply for various BA programs offered by the Delhi University or even honors in different regional languages like Punjabi, Sanskrit, etc. And if you fall under any category that is eligible for reservation like Sikh, SC, ST, OBC then your chances of getting a seat is even better.

All the Best!