Should I go for a degree in Computer Science at NTU or Business Administration at NUS? I don't know what's my passion but I'm highly adaptable and can do either?

Why don't you take a gap year and go do some internship in companies in these fields? At least, I would have wished I did my internship before Uni than during the last semester of my Uni, only to realise this is really not what I want.

1. Do you like to deal with people mostly? Or
2. Do you like to create stuff and like to try out new software?

1 => Go for BA
2 => Go for CS

Either one you choose, you'll still need to study further down the road while you're working due to changing nature of tech advances disrupting how business operating runs. So either choice quite safe as long as you carry on life long learning.

Cheers 😀👌🏼