Hi Forum
If you are on a UK base outside of the UK, then, in principle, you are not UK resident.
If you a Crown servant, such as HM armed forces, then as a crown employee, being paid by the UK government, your military earnings are taxable in the UK.
All other earnings, such as bank interest, dividends would not be taxable as you are not resident in the UK.
If you are for example the spouse of a person in the military and you have employment on the base, locally or work remotely for a UK employer, then this would be taxable in the country you are in.
Guidance is available at:
Tax for crown servants, EU employees and volunteer workers abroad
Thank you