This lesson is under the "Forcing moves" theme. Notice the text in the beginning states "White may even have a chance to win!" and then "check Black's king!", which by all logic means that when the user starts following the lesson's instructions, this will lead to white winning. Instead, after all the steps are done, the position gets completely closed and neither player can do anything worthwhile: therefore, after 50 moves without any captures, as per the rules of chess, the game will end in a DRAW and not a win for white as stated by the lesson. This is therefore an error in the wording of the lesson.
The lesson does not imply that you may be able to win. The "Saving Draws" lesson is exactly about finding moves which turn the game from a seemingly lost position to a draw.
In the lesson in question, "Saving Draws", the video begins with this exact line of text: "Chess is a game of many opportunities. Even when things look completely hopeless, you may find a way to turn the game around with a winning combination. Or if a win is impossible, you still may be able to save the game with a draw."
And in Challenge 5 of the lesson (which your post is about), the opening text is: "It's not everyday you can outsmart a computer chess engine, but in this amusing position, even though the engine thinks Black is winning, can you find a forcing bishop sacrifice that draws for White?"
I believe that the lesson and challenges are very clear. Like many games of chess, it is actually not possible to win a position with best play. Sometimes, it is only possible to look for drawing chances.
This lesson is under the "Forcing moves" theme. Notice the text in the beginning states "White may even have a chance to win!" and then "check Black's king!", which by all logic means that when the user starts following the lesson's instructions, this will lead to white winning. Instead, after all the steps are done, the position gets completely closed and neither player can do anything worthwhile: therefore, after 50 moves without any captures, as per the rules of chess, the game will end in a DRAW and not a win for white as stated by the lesson. This is therefore an error in the wording of the lesson.