Annotated chess game

It's obvious white has no idea what he's doing. He has no plan, and without a plan, prospects for winning are poor.

White continues to flounder without a plan, aimlessly checking black's king. "Patzer sees check, Patzer plays check".

This is a great example of the importance of having a concrete plan. White is clueless about what to do. Even though he had a winning position just a few moves ago, that advantage has now disappeared. Black on the other hand, was able to formulate a plan involving pushing his e-pawn supported by his K, and made useful moves accordingly, and now he has the winning position.

Ooops! Black has trapped his own king! This is now a draw. Instead of 55... Kf2, black needed to play Nf6->Nd5->Nf4, controlling the e2 square. In order to promote a passed pawn, it's important to first control the squares in front of it.

?? White can force a draw with 58.Rh1+ Kd2 59.Rh2+ etc. Black can't play ... Ke1 because of Re2+ winning the e-pawn.

White can still force a draw with 59.Rh1+ / 60.Rh2+ etc.

Does white see the perpetual check?

No! Despite having no clue how to play this ending, he's still trying to win! It doesn't really matter, the position is a dead draw now.

It's still a draw after 63.Bd3! and if 63... e1=Q 64.Bc2 is mate!

Does Black have winning chances if he promotes to a knight?

White can still stop the pawn with 66.a6 Nb6 67.c4 Nxc4 (white gives up a pawn to gain tempo) 68.Kc3 Nb6 59.Kd4 g5 60.Ke4. Note that black has to play 67... Nxc4, as otherwise, for example, 67... g5 68.c5 Na8 69.b5 g4 70.b6 g3 71.b7 g2 72.bxa8=Q g1=Q 73.Qe4+ white will be able to force the exchange of queens, and still have two passed pawns. But after 66.Kc2 g5, it's too late.

White is doomed now.