I tried to understand these short videos and watching it more than 3 times but couldn't get it could you help explain with details for these 2 questions

Watch these 3 clips from YouTube Clip about Monty Hall problem from movie 21

https://www.youtube.com/watch?v=iBdjqtR2iK4&t=7s

There are 2 clips that explain about the probability answer of Monty Hall.

Answer 2.1:https://www.youtube.com/watch?v=4Lb-6rxZxx0

Answer 2.2:https://www.youtube.com/watch?v=mhlc7peGlGg&t=256s

2.1 Which answer should be the one that actor in the movie explained about the Monty Hall? Give reason to support your selected answer.

2.2 Do you think that the probability knowledge from the Monty Hall can be applied in your real life? Clearly explain your answer.