While you can start with a purchased kit, I think it will only be the beginning for you. We each have such different needs and live in areas of such different risk that no pre-packaged kit can suit your need entirely.

The learning curve can be pretty steep at times regarding survival stuff. Build slowly and carefully. You learn fast, after a few mistakes with cheap, poorly made items, to buy only the best you can afford. Building your own kit, over the years, is a fun and satisfying project. I am always on the lookout for improvements or new items I can add to my various kits. Yes, you too will find that one kit is really not enough, you need different kits for the car, home, work etc, etc.