Question about Friedrich Nietzsche?

If you must, Nietzsche is more a writer in search of coherence than a kantian or hegelian systemizer. 

Some politely note Nietzsche was a "perspectivist"--aka an opinion-writer or editorialist.

His shtick was "My Pastor father unexpectedly passed on, God is dead, hello Schopenhauer, goodbye Schopenhauer, hello Wagner, goodbye Wagner, hello Zarathustra my sock-puppet tough love guru man that now I am, whoops, Mother, I'm Christ and Buddha."

A note from the man whom Friedrich cited as being his main teacher of psychological insight:  "Above all, don't lie to yourself.  The man who lies to himself and listens to his own lie comes to a point that he cannot distinguish the truth within him, or around him, and so loses all respect for himself and for others.  And having no respect he ceases to love."  Fyodor Dostoevsky, "The Brothers Karamazov."  "My father-God representative is passed on, and I'm not going to lie to myself that I'm a young man, when I'm but a child, nor that I know for sure 'God is dead'--rather, my father-Godly manhood is so seriously aborted at this juncture, that I'm unable to make the father-God I Am Presence realization that e.g. a bar mitzvah implies:  that one is both observant of the Presence or Law of God, and is thereof a capable moral agent"...and so young Friedrich goes on his brilliant, lifelong quest for the Overman, aka Emerson's Oversoul--the Godman within, the Presence of Brother Lawrence, which the good pastor re-Presents.  In this wise, Soren Kierkegaard's "Knight of Faith" is Friedrich Nietzsche, the overcomer finding faith in the God-Man (or, in Nietzsche's case, at least the Man-God) within, until mayhaps he begins to realize that both Christ and Buddha are aspects of the One Father-Mother, that Mohammad (owbp) can stand with Christ Jesus, as holy brothers, and that all less is "wrong path," even qua idolatry--God is the only Good, the One without a second.  Unclear as to whether he made the transition to what Berdyaev termed the God-Man of Dostoevsky (Man-God being Berdyaev's analysis of Friedrich Nietzsche, or the self-actualizer who doesn't yet discern a higher power (about 2-4% of Maslow's sample of self-actualizers).

The childish response, quite understandable for a brilliant and devout young child who loved his father, that of wretchedly crying "God is dead," is preferably early on healed, rather than developed into a lifelong search for the father-self within.  That Friedrich succeeded, is a testimony to his maslowian self-actualization models such as Goethe and da Vinci.  As Tennyson wrote, "An infant crying in the night An infant crying for the light And with no language but a cry."  https://en.wikipedia.org/wiki/Maslow's_hierarchy_of_needs  A contemporary of Friedrich Nietzsche who apparently suffered even more than Friedrich, albeit Friedrich Nietzsche, like Franz Kafka and others, has left a valuable written record of a human, all too human, suffering:  https://thoughtcatalog.com/jeremy-london/2019/06/kaspar-hauser/

So, to answer your question, if anything Nietzsche wrote inspires you, take that as a starting point to "explain" how Nietzsche justified.  In that mode, you're doing philosophy in the mode of Nietzsche:  giving a heart-felt opinion, and not taking "no" for an answer.  The bottom line of Nietzsche the philosopher:  any general statement he cares to give--an hypothesis--is "Because I said so."  Like Yoda.

Related:  other humans who endured and left records:

Man's Search for Meaning, Viktor Frankl;
Unbroken:  A World War II Story of Survival, Resilience, and Redemption, Laura Hillenbrand.

Sorry but I don't know anything about Nietzsche. Despite his "philosophy" he was just a man. This is what the Bible has to say about such men at 1 Corinthians 3:19 "For the wisdom of this world is foolishness with God, for it is written: “He catches the wise in their own cunning.”
When we live by Bible teachings, we become wiser than those who promote “the wisdom of this world.”