Please let me know what were bad moves at the beginning.
I am WalterMr ( White)

B11 is definitely bad. If white simply connects solidly, black's two-point extension on the right, which was already a somewhat thin choice, but still joseki, becomes even thinner. Try putting that position on a physical board, connect as white, and put yourself is black's shoes. Probably you would defend the black two-point extension, likely in gote, in which case white will have no trouble doing something else like counter-pincer.

Are you WalterMr or maxicat?

- Like snorri said, white should just connect. White could also try bumping at Q16, forcing black to play R15 and then white can make a bamboo joint at Q14. What's nice about this is that it leaves a cut for black at R14. But connecting solidly for white 12 is good enough. Hopefully you can see why the move white played in the game fails - it doesn't protect against the cut.

- Black should just play Q14. Then black's shape has no weaknesses and white's two stones on the outside are wasted. The situation would be good for black.

is a good cut.

has to protect the cut at R14. There are multiple moves that work to do this, such as S16 or just the simple R14, but one of them has to be played. Even if black had a guarantee that white would respond to with P13, this move wouldn't be good, as that exchange is good for white.

is nonsense. Black has to be willing to lose something at this point. Either black missed that his S14 stone was in atari or he misjudged the situation some other way, but the only move now is to capture the one stone at S13 and accept the unfortunate loss of the other three.

- it would have been better for black to have played here directly then to play and first. Notice how the moves they induce white to make actually makes it far simpler to capture black than it would be otherwise? Actually, Q11 is a better shape move for then Q10, but the best move may just be to tenuki and fight really hard in the remaining corners to try and catch up.

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