4-2 vs 3-3 (only pawn) endgames arising from Sicilian/Anti Sicilian I play Sicilian (mainly Najdorf) against e4. Sometimes (in anti-Sicilian or Sicilian openings) I end up with exchanging everything except 6 pawns.
So it becomes a 4-2 pawn (4 on the kingside) versus 3-3 end game. I am the side with 4-2 and most likely a6-b5 being the two.
I remember losing a few such games that I could have drawn or perhaps won.
Can you help me with the main strategies for black and and the opposing side white? Also in the specific game that I attached below, we reach to that position at move 28. But I appreciate any advice before move 28 as well.
[Event &quot;Rated Blitz game&quot;]
[Site &quot;https://lichess.org/wVcYyus2&quot;]
[Date &quot;2020.09.02&quot;]
[Result &quot;1-0&quot;]
[UTCDate &quot;2020.09.02&quot;]
[UTCTime &quot;18:34:04&quot;]
[WhiteElo &quot;2174&quot;]
[BlackElo &quot;2033&quot;]
[WhiteRatingDiff &quot;+3&quot;]
[BlackRatingDiff &quot;-3&quot;]
[Variant &quot;Standard&quot;]
[TimeControl &quot;300+0&quot;]
[ECO &quot;B22&quot;]
[Opening &quot;Sicilian Defense: Alapin Variation, Barmen Defense&quot;]
[Termination &quot;Normal&quot;]
[FEN &quot;&quot;]
[startply &quot;54&quot;]

1. e4 c5 2. c3 d5 3. exd5 Qxd5 4. d4 Nc6 5. Nf3 Bg4 6. Be2 e6 7. O-O Nf6 8. Be3 cxd4 9. Nxd4 Bxe2 10. Qxe2 Be7 11. Rd1 Nxd4 12. Bxd4 Qc6 13. Nd2 O-O 14. Nf3 Rfd8 15. h3 Rac8 16. Ne5 Qc7 17. a4 Nd7 18. a5 Nxe5 19. Qxe5 Qxe5 20. Bxe5 a6 21. Kf1 Kf8 22. Ke2 f6 23. Bd4 Ke8 24. Bb6 Rxd1 25. Rxd1 Bd8 26. Rxd8+ Rxd8 27. Bxd8 Kxd8 28. Kd3 Kd7 29. b4 Kc6 30. c4 g6 31. Ke4 b6 32. axb6 Kxb6 33. f4 h5 34. g4 hxg4 35. hxg4 Kc6 36. g5 f5+ 37. Ke5 Kd7 38. c5 Kc6 39. Kxe6 Kb5 40. Kf6 Kxb4 41. c6 a5 42. c7 a4 43. c8=Q 1-0

EDIT: Brian’s answer well addressed the case when my king’s position was inferior but I am actually more curious about the strategies in the case when they are the same or mine is superior. In the game below, I have a superior king position, but then I blunder. What should be the strategy of black in that case? Instead of pushing the a-pawn, I guess I should have done f6 to avoid g5. Then should I try pushing e5 to make it a passed pawn? But then wouldn’t it be an isolated, hence a vulnerable pawn? Again any comment before the start ply will be also useful.
To put it another way, considering the respective start plies in those games,in the first game, what to do to hold a draw, and in the second, what to do to win strategically?
EDIT 2: After Evargalo and David’s comments, I am more or less ok with the first game in the sense that there is no much more to say.
But as Evargalo pointed out in his comment, I don’t quite see why I had +0.9 in the very last position of the second game. To compare, I think both sides violated the second principle of Brian (don’t play in the minority side) and I think I had a better king position. My guess is that it could be due to losing the opposition or the g pawn blocking both f and h. But a deeper perspective could be better.
EDIT 3 After Brian’s great answers and my analysis with Stockfish, I seem to get an idea. But even then pawn endgames are very sensitive to mistakes that might be hard to spot. Thanks to all the contributors.
[Date &quot;2020.09.02&quot;]
[Result &quot;1-0&quot;]
[UTCDate &quot;2018&quot;]
[UTCTime &quot;&quot;]
[WhiteElo &quot;&quot;]
[BlackElo &quot;&quot;]
[WhiteRatingDiff &quot;&quot;]
[BlackRatingDiff &quot;&quot;]
[Variant &quot;Standard&quot;]
[TimeControl &quot;&quot;]
[ECO &quot;&quot;]
[Opening &quot;&quot;]
[Termination &quot;Normal&quot;]
[FEN &quot;&quot;]
[startply &quot;70&quot;]


1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Bc4 e6 7. O-O b5 8. Bd3 Bb7 9. a3 Be7 10. Be3 O-O 11. f3 Nbd7 12. Qe1 d5 13. exd5 Nxd5 14. Nxd5 Bxd5 15. c3 Qc7 16. Rd1 Rad8 17. Qf2 Ne5 18. Be4 Qb7 19. Bxd5 Rxd5 20. Ne2 Rfd8 21. Rxd5 Rxd5 22. Nf4 Nd3 23. Nxd3 Rxd3 24. Bd4 Qd5 25. Qg3 g6 26. Re1 Bd6 27. Qh4 Bc5 28. Bxc5 Qxc5+ 29. Qf2 Qxf2+ 30. Kxf2 Kf8 31. Re3 Rd2+ 32. Re2 Rd5 33. f4 Ke7 34. Ke3 Kd6 35. Rd2 Rxd2 36. Kxd2 a5 37. g4 a4 38. g5 Kd5 1-0
King and pawn endgames are much easier than ones where each side also has a rook. The key principles are fairly simple. You want to try and queen a pawn. With pawns on both sides of the board and an imbalance as here there are two key points:

Getting your king to the middle of the board is very important.
The only pawns you are likely to queen are ones on the side where you have the majority. If the kings keep away then the further up your pawns get the easier it is to get a passed pawn and queen. So, don't move pawns on your minority side unless you absolutely have to! Doing so makes your opponent's task easier. Move pawns on the side where you have the majority.

In the position you show after move 27 you are already behind in the race to centralize your king. Whether that means you were already losing I doubt but it does make things difficult and it was your choice. Your king has taken 3 moves to go from g8 to d8. In the same number of moves you could have gone from g8 to d5 and that would have been a very different story.
Your transition into the endgame was very poor. Perhaps 20...a6 was already a mistake. You are breaking rul2 by advancing a pawn on your weak side. Better would have been f6 which as well as being a free move, because it kicks the bishop, frees f7, which is a much better square for your king than f8, and moves a pawn on your majority side.
After 24. Bb6 you are in too much of a rush to get all the pieces off with RxR and Bd8. You exchanged pieces in a way which was good for your opponent and bad for you. Bd8 was particularly bad. Your rook on c8 paralyzes white's queenside pawns.
Suppose instead it had gone something like this after move 20:
[fen &quot;2rr2k1/pp2bppp/4p3/P3q3/3B4/2P4P/1P3PP1/R2R2K1 w - - 0 1&quot;]

1. Bxe5 f6 2. Bd4 a6 3. Bb6 Rd6 4. Rxd6 Bxd6 5. Rd1 Rc6 6. Kf1 (6. b4 Bc7) Kf7 7. Ke2 e5

After 5...Rc6 you have a simple plan of bringing your king quickly to the center with Kf7, e5, Ke6. If white tries immediately to kick your rook away from the defence of the bishop by rushing forward the queenside pawns starting with b4 then Bc7 is a good response.