The Gabridoodle does something that might seem highly counterintutive to a noob: leaving his queen exposed to Pinkums' rook. In fact, he does this not for one move, but for two. This is okay because each time he has a zwischenzug (in-between move) that's also a forcing move.
Since this is a "noobs lesson," actual chess jargon is in red.
...instead, knight to f4 (maybe we should say "knife to f4") wins even more material. This forks Pinkums' queen and king (a royal fork). She moves her king to e3. Note that moving her king to d2 instead wouldn't save her bacon as the Gabridoodle would just give check with his queen and proceed with his plan.
The Gabridoodle now snaffles up the white queen with his knight/knife, a move that also gives check ! No matter how she saves her king (either moving it or capturing the Gabridoodle's knight/knife with the pawn), her rook now falls to the Gabridoodle's queen.