I served 10 years+ in the British Army. The MOD is a completely different kettle of fish, your best bet is to join the Reserves (TA) first although even that isn’t the same… Unfortunately there is no job in the world similar to life in the British Army and the only way to know is to take a leap of faith. It’s not everyone’s cup of tea but if you enjoy it, you will form your fondest (and worst) memories of your life there.
Hope this helps
John Cormack