Another word for no regrets is impenitent.
Impenitent means to not have any regrets or feel any shame about one's attitude or actions.
Examples of impenitent in a sentence :
-The bully was impenitent when he pushed the little boy off the swings.
-Julie's impenitent attitude after reading Sara's diary in front of her whole class, led to detention from the Headmistress.
Answer:yes
Explanation:
because know the past can help you build what you know now
"it's" is the correct form