Dear student,
Bcom computer application is an undergraduate Commerce course. Bcom in computer application is generally  a three academic year degree course and may also differentiate from place to place.
Bcom computer application eligibility :

• A candidate willing to have Bcom course in a subject must have obtained a minimum of 50%marks in the aggregate and 45% marks in the subject or related subject at the previous qualifying exam.
• Candidates who have passed the Higher Secondary  (10+2) Vocational examination in business and Commerce.

Hence if you're from science background i don't think it will be possible for you.

Thankyou.