Having taught courses on interview techniques, I'd say the quick advice is - remember that for all the questions they ask, they are not primarily interested in you answering the specific question, they are trying to provide an opportunity or a challenge to hear how you fit their idea of a good candidate for the post.

So they don't care about knowing you as a person, they want to hear you're "innovative" or "ambitious" or "compassionate" (depending on the post), with a little anecdote or explanation that shows you understand what that trait means. "I guess some people might call me driven, because from a young age I've always want to be the best at everything. But personally it's not just about being 'ambitious', when I'm passionate about something then I really want to do my best at it, that's why I love learning new approaches and methods to improve my skills, and love working in an industry like ours with so much potential. And from what I understand about your company... " blah blah blah.

It defintely doesn't need to be all bragging and corporate speak (unless that's your work field) but most people do better at interviews once they realise the questions are just the superficial layer, and yoh don't need to worry about them too much. You should answer them (otherwise you seem like you have poor communication skills) but the content of them is just your chance to show off skills and qualities that they want, and to show you understand the job and industry you're in. Having a close read of the job description, company's values and other info should reveal a bunch of target traits that they want to hear about from you.