Michael, is there a "general" rating range for each of these forums?
Intermediate Forum

this was a win for me, my strengths were that at the start of the endgame (queen trade?) I had a 1 pawn advantage, better pawn structure, and my king is more free to move than my opponent. I did not feel any weaknesses here.

Here is my loss, against a higher rated player, opposite my win, my weaknesses were that I was down two pawns, and poor pawn structure. For me this endgame was lost when it went into the endgame because of poor positional play in the middle game.

In this last game I entered the end game down 2 pawns but was able to neutralize that advantage and earn a draw. Overall I think that my endgame weaknesses stem from problems with possitional play in the openings and middle game.

I guess in the game you lost 23.Qd3 is not the best move. Qe3 or f4 are perhaps better. Giving more chances to survive the endgame. The other games are good from where i am standing.

Above my loss from a won game (I think) two major blunders, at move 28 I missed his N guarding e1 and then worse at move 30 a Q rook fork blunder.
I hoped to stalemate in the endgame but was outplayed

47. ...Rxa2+ 48. Kxh3 Ra3+ 49. Kg2 Re3. And on the next move Rxe5. Might still be a draw but better chances for black i think.
Here you can post your work for the week and discuss endgames with those who are in a similar place that you are in their endgame studies.