Many characters, in particular Churchill, are shown drinking and smoking in various scenes.
in 99% of the scenes with the main Character he is shown drinking various liquors, pouring a glass, asking for refills, etc.. When asked how he can drink throughout the day and manage he responds "with a lot of practice". Another quips that Churchill has alcohol for breakfast, lunch, dinner, and dessert.
The main character is shown at all times with a cigar - either smoking it, lighting it, looking for matches, etc. He quips to his wife maybe he could cut down from smoking 4 a day.