How to take flawless pictures?

I have a Nikon D90 and I absolutley don't know how to take flawless pictures.
Here's an example:

Added (1). I tried once but you end up seeing my blemishes, the flake of my makeup, and etc.

You can take pictures like your example with pretty much any camera made in the past ten years that has a built in flash. Put it on the green fully automatic setting and push the button.

This isn't the worst photo I've seen, but it's close.

It is not the camera… You can have the most expensive camera in the world and take bad shots.
I'm not sure there's such a thing as flawless photos. If there's you can bet that there was a lot of photo shop involved.
Buy a book on lighting by Peterson… Think first name Brian but not sure.
Study photos study the way the light hits the subject. No one takes flawless photos right off the bat… In fact those who have been in the business for years are still trying.
Rule 1--PRACTICE PRACTICE PRACTICE.
Rule 2--PRACTICE PRACTICE PRACTICE.
Learn your lighting -aperture shutter speed.use manual shooting do not depend on the camera. Get a light meter.
Learn the rules of photography so they are natural to you when you use your camera. But remember the rules of photography are NOT cast in stone. Break them now and then.

The camera isn't going to take the pictures for you, the best thing to do is learn something about photography and then practice. If you're expecting to be good overnight you'll be very disappointed.