im totally confused about which core subject of computer science should i apply for. can anyone advice?

Answer 1

what are your options and what are your interests? e.g. I m hooked about algorithms (mainly approx algorithms and tsp in general) and despise Web development to some degree (currently working on that though).

without further info no one can really answer your question though

Answer 2

I'm confused whether its better to go coding side or data side @petja Boigk