We often get these questions during the rishta process from aunties and girls who're fascinated by the military charm. Is something like that going on? Are you marrying an officer or someone else you know, bro?
I'm kidding.
Each force's mess is a little different and each force has their own traditions. We have a manager and members who help devise the food menu keeping in view nutritional requirements, local produce available, number of mess staff, gas etc., so you'd find a wide ranging menu.
If the mess is big such as of a base or brig hq then you'd have something akin to a self-service mode. Usually juniors take their food but seniors are served by a waiter even if it's self service. If the mess is small then you can have custom orders and also depends on working routines, sometimes you can't go to the mess so the food'd come to you.
The food is like the food you eat. Eggs and roti/ bread/ paratha for breakfast (If you want you can order a cereal too but usually forces sees a heavy breakfast because who doesn't? lol) lunch is usually a vegetable based dish such as daal, maybe haleem, masar chawal etc., lunch is protein based, qarai, boneless handi, etc.,
Once every week we've burgers, pizza, lasagna etc (western crusine)
And Army, Navy or Air Force. Friday, lunch is the biryani and if your mess can make good biryani, you'd be the envy of other set ups.