How can I watch a downloaded movie from Itunes in airplane mode??

I have an Iphone 11 Pro. I have and purchased movies for an upcoming trip. I hit the download button and now when I go into Itunes then library I can see the movie there. However, to test this I have put the phone in airplane mode. When I do this, I cannot access Itunes to view the movies. Surely once the movies are downloaded to the phone itself there is a way to access and view them without having wifi. What am I doing wrong?

Is there another way to select and download movies other than Itunes? I have heard you can also download movies from the Netflix app as well but not sure how to do that or then view the movie once airplane mode is on.

Thanks for any help in advance.