Yes they can. However joining as an Officer would require you to have 3 years residencey prior to joining but as a soldier you can join almost immediatley upon entering the UK.
Depends if the country is commonwealth
Yes. Nigeria is part of the Commonwealth
YES
No, The only people who are eligible to join the British Army are British Citizens, who are born in Britain. Citizens of Nepal can join the Brigade of Gurkha's. Commonwealth Citizens may join the British Army, if they meet all the elibility.
Fiji is a Commonwealth nation. Any citizen of any Commonwealth nation is permitted by British Army regulations to enlist in the British army, so long as their country was in the Commonwealth at the time of their birth (thus, a citizen of Zimbabwe who was born while the country remained in the Commonwealth is still able to enlist in the British Army, even though Zimbabwe is no longer a member of the Commonwealth of Nations).
No. You have to meet the citizenship requirements of the british army which includes nationalities other than british (E.g Commonwealth nations)
Yes, any Irish or commonwealth national can join the British armed services, although an oath to HM the Queen is mandatory.
Yes Uganda is a Commonwealth nation. Any citizen of any Commonwealth nation is permitted by British Forces regulations to enlist in the British Forces, so long as their country was in the Commonwealth at the time of their birth (thus, a citizen of Zimbabwe who was born while the country remained in the Commonwealth is still able to enlist in the British Army, even though Zimbabwe is no longer a member of the Commonwealth of Nations).
The British Armed Forces accept citizens of all Commonwealth nations (whether a Dominion, or just in the Commonwealth of Nations), as well as citizens of nations who may no longer be in the Commonwealth, but were at the time of the individual's birth (for example, a citizen of Zimbabwe could join the Royal Army so long as they were born prior to Zimbabwe's withdrawal from the Commonwealth of Nations). So, your short answer would be yes.
Jamaica joined the Commonwealth Games by being a member of the British Commonwealth.
Jamaica joined the Commonwealth Games by being a member of the British Commonwealth.
If Mauritius is part of the commonwealth