How is the rook and queen fork NOT the best move for black?! Computer wants a5 : r/chessbeginners

In this position, (black to move) Qe1 is apparently checkmate, but

Chess For Beginners 0241538432 9780241538432 PDF, PDF

Chess Noob - The Fork

Queen Fork-o-Rama

Principles of Attacks in Chess

Starting Chess? Your Ultimate Rule Guide Awaits - Remote Chess Academy

Black's defense looks solid, and the pieces around the king formed

Fork in chess

Black to move in a sticky situation : r/chessbeginners

Principles of Attacks in Chess

KNIGHT FORKS Diagram 93 - Black wins a Rook for a Knight--or the

The Rook Fork - Moving the King into Position