Complex sentence: For all combat personnel who either join Armour as a regular or by being posted to Armour after basic training, there are two main combat vocations within Armour: a Tank Operator and the other is being an Armoured Infantry.
Split into simpler sentences: For all combat personals who either join Armour as a Regular or being posted to Armour after basic training. One is being a Tank Operator and the other is being an Armoured Infantry.