White has space advantage on the Queen side, more active minor pieces and a slight edge in initiative. Black is congested and his Bishop is passive compared to either Knight. This gives a slight edge to White since Black cannot break the center and would have to find a break through on the King's wing, likely with a sac, which would likely present itself say, from a blunder by White. That's just my take on it
How is White Better in this Position??!

"The computer analysis says white is better at move 28 till the opponent blunders? How can this be?"
It can be for the following reasons:
More space.
Better pawn structure.
Better minor pieces.
This is why you shouldn't use an engine if you don't understand how, or when to use one.

White's kingside pawn structure is devastated leaving the king totally vulnerable to attack. Moreover the doubled pawns on the e-file prevent white's queen and rook from intervening in the defense. This seems like black at move 29 should be +3 at least.

"White's kingside pawn structure is devastated leaving the king totally vulnerable to attack."
What "attack" are you referring to?
"Moreover the doubled pawns on the e-file prevent white's queen and rook from intervening in the defense."
A weakness is only weak if it can be attacked.
"This seems like black at move 29 should be +3 at least."
Like i said before. You shouldnt be using an engine.
The computer analysis says white is better at move 28 till the opponent blunders? How can this be? Is the computer analysis wrong?