How can one stop the sin of cursing a parent, which is believed to be the cause of delayed provision and bad luck, due to the parent preventing work opportunities and refusing to provide money for a private project?

Insulting one's parents is a major sin, whether one causes them to be insulted or insults them directly. Allah Almighty has forbidden even uttering the word "uff" to them. As for scarcity of sustenance, it is in the hands of Allah, and sustenance is decreed for a person and will come to them; indeed, sustenance seeks the servant more than their appointed time of death seeks them. Maintaining kinship ties in general is a cause of abundant sustenance, and a primary cause of it is filial piety towards parents. Happiness in this world is not about abundant wealth, but rather about faith, contentment, and satisfaction, and this world is contemptible in the sight of Allah. Do not despair or grieve over a lack of money, and look at those beneath you in worldly matters to realize Allah's blessings upon you. Be content with Allah's decree and predestination in the distribution of sustenance, and rely on Allah through supplication and humble entreaty, especially during the last third of the night.