Compare: كَتَبَ حَامِدٌ الدَّرْسَ means “Hamid wrote the lesson.”
With قَدْ: قَدْ كَتَبَ حَامِدٌ الدَّرْسَ naturally means “Hamid has written the lesson.”
Do not begin by assigning one isolated English word to قَدْ. First notice the past verb and the context, then express the completed or emphasized meaning naturally.