Help with understanding why my moves were bad (and variations I thought were very cool in this game)

The game in question: lichess.org/55NheREs/white#1

So, for some of the moves that were deemed mistakes by the computer, the advantage White (me) gains is basically something that for my skill level is very hard to spot as a mistake. Basically, by sacrificing material I gain a position where black is almost in zugzwang the entire time and White wins eventually. (This is I think the second mistake in the "Learn from your mistakes" section)

So, could you help me explain more why all of these moves were mistakes? And what do you think of the variations, if you have interest / time to look?

I don’t think anything was too bad apart from the check mate in two from black.

you should upload your losses game, not winning.

18. Qxe6 is better than 18.Qc2 because after 18....,fxe6, Black has a weak isolated double pawn on the e file, White threaten to take control of the open d file by doubling the rooks and the knight on f6 is pinned. The e5 pawn seems doomed.
19.c4 is maybe better than 19.Kh2 , at least from a human point of view, because it tries to create weaknesses in the black pawn structure if black takes the pawn, i.e. two island of isolated pawns. It is not really a sacrifice because the c4 pawn will fall.

This is a bullet game there is nothing to analyse

Black was never remotely near Zugzwang. Not sure what you mean.