“When everything seems to be going against you, remember that the airplane takes off against the wind, not with it.” –Henry Ford
Inside, human beings are of good nature!
A complete sentence invariably has a preposition of one or the other: of and off are commonly used, so is the case with from; refer to a standard dictionary, and take note of their usage when you read texts.
Of is a preposition, and has multiple meanings, and the Oxford dictionary lists more than two dozen meanings, and so is the case with ‘off’.
Of means about, like, regarding, concerning, belonging, and is one sense also means from; tells us about the belonging to someone or something and is usually followed by possessive pronouns (She is a relative of his. He is friend of hers.).
Of indicates to a distance, direction, separation, deprivation (South of India is Sri Lanka. Age will rob you of your mobility and memory unless cared for. The vedas of ancient India have no authors. You like basin of biryani or bowl of fruits? People befriend with people of different social backgrounds).
Off refers to indicate cause, motive, reason, apposition, identity among others.
Are you suffering from fever, or, are you suffering of fever?
You are suffering from fever.
You are of a wonderful nature so suffering from illness are coped.
People are prone to suffering from one or the other disease.
India is need of equal opportunities for all, and it is suffering from inequalities. How can it relieve the country of its inequalities?
Of is also used sometimes to phrases beginning with the adverb: How long of a walk/drive to get there? Day is of darkness and light.
The usage of ‘of’ and ‘off’ has formal and informal ways in speech and in writing, and depends on context.
Off has multiple meanings, and has a multiple roles as a parts of speech (preposition, adverb, adjective) in addition to forming phrases and phrasal verbs: Well-off people! Better-off. On and off.
Off functions as an adjective with words like after, rather, very, slightly, etc especially informally: off-side, she is off with him on social media; something no longer fresh or good (the potatoes have gone off or gone bad).
“If you worried about falling off the bike, you’d never get on.” –Lance Armstrong
Where do you come from? From indicates the place, direction, time, origins, reasons for something or for a cause and many more.
You are better off to learn independently as well, and, of course with practice: you shall make very good use of your gifts.