Will a father be punished after his death if his unmarried daughters, who were under his care, are immodestly dressed and do not wear the hijab? And if so, can a da'wah (preaching/invitational) word be directed to these girls?

Among the father's duties in Islam is to raise his sons and daughters to obey Allah and protect them from prohibitions, including enjoining his daughters to observe hijab and preventing them from tabarruj (displaying their adornments). He is responsible for his flock and will be held accountable for his negligence in teaching them about their religion. If he falls short in this, he is in grave danger. However, he is not definitively condemned to otherworldly punishment, for he might be forgiven, or he might have good deeds that erase his sins, or he might be excused. As for one who enjoins his daughters to observe hijab to the best of his ability, but they do not respond to him, he has fulfilled his duty and will not be punished for their sins.