as a noun, 'due' refers to something that is owed or that needs to be paid.
Membership dues are to be paid annually.
He always pays his dues on time.
After years of hard work, she finally got the recognition she deserved; she paid her dues in the industry.
'Paying your dues' is an idiomatic expression meaning to spend time in a low-ranking position or situation, deserving of a better position in the future.
Don't confuse 'due' (something owed) with 'do' (a verb indicating action).
as an adjective, 'due' describes something that is expected or anticipated, often within a specific timeframe. It can also refer to something that is appropriate or deserved.
The report is due tomorrow.
Respect is due to those who have earned it.
The town is located due north of the city.
Be cautious about the difference between 'due' and 'do.' They sound alike but have different meanings. 'Due' can also be part of the phrase 'in due course,' meaning in the appropriate or expected time.