I think it was an old movie (like 1940-1965) about a man who was – I think – discharged from the army or just lied about being a veteran, he made up something, fake medal etc. Anyway he comes back home and the family thinks of him as a war hero and he doesn’t mind so the lie goes on until it’s too much for him. They want to hear his stories etc. It was some kind of satire or comedy of errors.
I’m not sure everything I wrote here is correct though.