We must ask ourselves, will our actions help or harm others? If they are harmful, then those actions are not dharma. When this point is clear you will always understand what your duty is.
Our parents have brought us into the world and fulfilled their duties towards us, so we have duties towards them.
We have obtained benefits from society so we have duties towards society. There are many unseen factors that act to help us and these factors also must be recognised and acknowledged.
When you keep your mind on your duties you will find that your mind is never idle. When you have debts to pay, there is much to attend to. Only idle minds develop imaginings based on inclinations, likes and dislikes.
Duty is the debt paid for what is gained. All of us have gained from God, society and our parents, so duty is required in return. Duty should be done for duty's sake.
Duty is something you attend to whether you like it or not. No parent actually enjoys changing diapers, but a baby is helpless and totally reliant on its parents, so changing diapers is one of their duties, like it or not.