B.Sc

Yes, you can apply for B.Sc. Computer Science (Hons.) at DU with your commerce background, only if you studied Mathematics in Class 12. 

Subjects you can take in CUET for DU:

1 Language (from CUET List A)

Mathematics or Applied Mathematics

Any two domain subjects from Section II (Computer Science, Physics, Chemistry, or Economics)

No

Sandhu Institute of Nursing itself does not offer its own scholarships for B.Sc. Nursing students 

In Trivandrum, you can pursue B.Sc. Food Technology at University College (Palayam) or Sree Narayana College (Chempazhanthy). These are affiliated with Kerala University, admit via +2 Science merit (usually 50%), and offer a 3-year CBCS-based curriculum. Seats are limited, so apply early through KU's centralized admissions portal.

If you're planning to do B.Sc at DAV College Chandigarh, the fee for general students is somewhere around INR 25000 to 35000 per year, depending on the subject. For SC, ST, or EWS students, the fee is usually less, and in many cases, there are scholarships or full waivers available. It really depends on your documents and income status. Best thing to do is check directly with the college when admissions open — they'll give you the exact numbers.