Why is my move (g6) is a mistake in this game?

In this game (I am black, the opponent is white and I won and the link is https://www.chess.com/game/live/5486042146) why the 10th move g6 is shown as a mistake in the analysis? (Link to analysis: https://www.chess.com/analysis/game/live/5486042146)

Here is a screenshot of the board and to recall you again the mistake is g6 and my question is why is that move a mistake?

Thank you very much for helping me. Is computer analysis smart enough to consider exposing king's file as mistake? And is this the reason in my case?

It would be also helpful if you tell me that if you were in my place, what move would you choose to defend the bishop? Thanks

i would play be6 because when you have the isolated pawn you generally want to avoid trading minor pieces.

You should just trade on d3. And the problem with g6? is not only your King position but your Pawns on the Kingside are vere weak after gxf5 (= they can't defend each other).

I think you misread the board. There are no isolated pawns.

Okay, it seems that there is no better way than trading on d3. Am I right?

7 months later I am no longer a player of 658 rating now. My rating is near 940 now and it's totally obvious why g6 is a bad move

that is nice, ain't it!

Yes

Those dark squares be lookin pretty weak tho

Double your pawn