) when we pray to Him, we are to "enter into thy closet, … shut thy door, [and] pray to thy Father which is in secret"; (f) then "thy Father which seeth in secret ... shall reward thee openly."

When Jesus gave us permission to address His Father as "our Father which art in heaven," He gave us complete confidentiality with Him.
He emphasized secrecy (Matt. 6:1-6): (a) We are not to make our acts or gifts of worship to be "seen of men"; (b) we are not to seek "glory of men"; (c) we are not to let our left hand know what our right hand does--here again is ultimate secrecy; (d) thy " Father … seeth in secret"; (e) when we pray to Him, we are to "enter into thy closet, … shut thy door, [and] pray to thy Father which is in secret"; (f) then "thy Father which seeth in secret ... shall reward thee openly."
The word "Father" brings up the most tender memories of our childhood, yes, babyhood. The first syllable we could utter as a baby was "ba"--which became our "Ba-ba."
We revered our earthly father; as children he stood to us in the place of God. Yes, his task was to reveal the heavenly Father to us, and to interpret to us aright His love, His fidelity.
This is the idea in Romans 8 where we read, "Ye have not received the spirit of bondage ... to fear; but ye have received the Spirit of adoption, whereby we cry, Abba, Father" (vs .15).
Our first cry as a baby is not "Abba, Father," but "abba, father." We don't know yet to cry to God; our earthly father interprets God to us.
If he is a God-reverencing person, kind, unselfish, loving, then he is interpreting the love (agape) of the heavenly Father to us. Rejoice and be exceeding glad; you are very fortunate.
Sometimes an earthly father does not know how to interpret to the child the love (agape) of the heavenly Father. In those cases it can become emotionally difficult for the person to learn to be happy "in Christ"; but don't turn away, never, not for a moment. Let your heavenly Father intervene: He is much, much greater than your earthly father; His influence in your life is out of all bounds far greater than the influence your earthly father was to you; yes, let Him into your life.
Share with Him alone (that's what it means that Jesus said, "shut your door to your closet"), open your heart with all your shame and guilt. Your heavenly "Father seeth in secret." He alone is your true "Father-Confessor." Pour it all out to Him "in secret"; He will reward thee "openly," that is, with full salvation, healing, in Christ.