Can bad kammas be eased by apologizing? For example if I have lied to my parents and can the bad kamma be deleted when I apologize to them? 

What is the difference between the bad kamma that are committed to parents and ordinary people?
Apologizing is good Karma that has a mitigating(not delete) effect on the bad Karma you had committed:
ex:


The story of Soreyya.
Devadatta taking refuge of the Buddha just before being swallowed by earth.
The story of Bhaddā Kapilānī Therī


Bad Karma committed against parents are highly potent compared to ordinary beings. Ex: Killing parents makes birth(next life) in hell inescapable and you will have to face the consequences in the subsequent lives until you end Samsara.