Is white or black winning in this position?
How can anyone see which side is on move?
Look at the FEN in the pgn? Looks like it says Black to move: rnb1kb1r/pp2nppp/3p4/2qNp3/4P3/5N2/PPP2PPP/R1BQKB1R b - - 0 1
What if it was white to play, would it still be equal, or white/black is winning?
If it is White to move then White wins with 1.b4!
Assuming black to move, I'd say white is a bit better. Black's middle pawns are kinda awkward, d6 will be a weakness. Black's dark squared bishop is blocked and fianchettoing keeps it blocked by those same awkward pawns. Black's queen will get kicked with tempo by White's bishop. White has an unkickable knight at d5, black probably trades to get rid of that. All that said, it's still a small advantage. As Hikaru says all openings are playable. Black can surely hold a draw with best play, but White is the happy one here.