No draw

A game was declared draw , however the situation was a bishop and king for white, a queen and king for black. Black's clock goes to zero. This should be won for white, as there is a mate combination possible. It is declared draw. this is wrong.

It isn't possible to mate with only a bishop against a queen.

A bishop can't even mate against a rook. By extension, queen makes it impossible too.
Opposite-color bishop is the only piece that can allow such mate.

Which makes me think... will a non-rook pawn make it a draw when the promotion square is same color as the bishop's?

#3 No: anything can mate a knight.

What happens if black's clock runs out after white makes his 300th move on Lichess?

You are right. I forgot the bishop can check touching the king.

Story of my chess. I keep rebuilding everything I once learnt.

@RapidVariants #4 : After Black makes the 300th move, it is automatically called a draw. See an example game here: lichess.org/xzobgcPZ/black#600

@thechessguy2_0 That's my point: what if black runs out of time before making the drawing move? He cannot possibly get checkmated, since white wouldn't be allowed to play his 301st move.

But I do't see any time on this game.
Why is it a draw?

If somobody have no pieces and he or she play fifty movies with no pieces then it is draw