This little film gives a very good idea of what things are like on subs - it’s from 1986, but I doubt the human stuff, teamwork, have changed much. Tom Clancy looks very young here - it’s said that he was very impressed with the food he enjoyed on submarines.
Some interesting points are made by the British historian who says that the caliber of men and morale are far more important than machinery; and that, with the advent of the German U-Boat, many people thought that submarine warfare was immoral and underhanded. It’s about an hour long:
https://www.youtube.com/watch?v=7Qt7dyhB-jg
I just watched an excellent Hollywood movie called “Enemy Below” starring Robert Mitchum and Curt Jergens and learned “Das Boot” was a total ripoff! I don’t remember any food being served in the movie but I do recommend it. Mr. Jergens steals the movie as the captain of a German sub.