Why does white have an advantage of +0.06 in this position

White is a pawn down and it has doubled isolated pawns..

In this position, black is to move.

In my opinion even if the computer was capable of explaining to you why, it would be of no practical use, even to the very best of players. Both the point values of the moves shown, along with the order of multiple lines are all prone to change. A line can be replaced with a new line. What you see is not chiseled in stone but changes.

As in your game for example I clicked on analysis 4 times. In this case Nd5 was consistently the best move in the following order -0.06, -0.03, -0.04, then changed to whites favor with a 0.9 discrepancy from the first click to +0.03.

First click showed Rc8 at +0.05, And the third line Rd8 at +0.04 The second click and those lines inverted with Rd8 at +0.27 as the second line and Rc8 at +0.16 as the third line.

I suppose it's because: White has their countreplay. For example, they have better developed pieces, their king is castled, which means their rooks are closer ro be connected than the opponent's, and in addition, they have a half-opened file b, which they can use for rooks with help of their bishop g2. For example, if it was white to move, they could play Rb1, and black would have no way to save that pawn as: b6 doesn't work for obvious reasons. Rb8 as well, as their pawn is now pinned and we can win their pawn. It's black to move rn, and they are free to do whatever they want, but white still has this possibility of Rb1, and black has a hard time to develop their bishop, castle their king, and connect their rooks

In my opinion, the reason why the computer would think this game is quite balanced (which is what +0.06 indicates) is because Black has 1 pawn more, but White's pieces are better developed. White has a rook on the open d-file and they've got both bishops available to use on large diagonals. If they move their dark-squared bishop off the back rank, then the rooks are connected and White is ready to attack.

Black on the other hand has a bishop that isn't yet ready to do anything, their rooks are stuck in the corners and their king is not castled. This difference in development probably compensates for the material difference and the double pawn. (That's my interpretation! :-))