This is a type of the BBCBASIC World War 1 game given in to the "Book of Games" 1985 by Adam Mastromarino
It's possible that this has been printed incorrectly in the magazine or typed up incorrectly afterwards by Merlyn-Cooper. When the game is running an issue occurs on a line that is in a loop so without being able to debug it it's hard to know what is happening.
If someone can suggest a valid IDE that would be appreciated.
https://archive.org/details/Book_of_Games_1985-02_EMAP_Publishing_GB_supplement_issue_040