Hello student both are equally good in their respective places it's upto you in which you're interested, if you're interested in Science stream and want to continue further studies after Bachelor’s in Science then you should go with BSc computer science otherwise you can choose Bcom computer science. In Bcom computer science computer science is a subject and you have to study commerce stream subjects like Economics Accounts law etc. So if you've interest in commerce and you're from commerce background then you can also choose Bcom computer science.

Generally science background student don't prefer Bcom computer science because they have to go with the very basics of commerce subjects (specially Accounts).

Feel free to comment if you've any doubt

Good luck