Buddhism is not fatalism. It doesn't teach that everything that happens to you is fated. In fact, it teaches the opposite. (SN 36.21)
Yes. You inherit your genes from your parents and you inherit part of your ideas and knowledge from your environment, country, books, teachers etc. This is called "old karma" in the suttas (SN 35.146).
You experience the results of your past karma but not all that happens to you is caused by kamma, says that suttas. For e.g. some things are caused by the weather or bile or wind or somebody hurting you. That's not caused by your karma. (SN 36.21)
The mind precedes all states (Dhp 1 - 2). Karma starts with the mind.
Karma is always based on intention. ("Intention is kamma. Intending, one does kamma by way of body, speech, & intellect." - AN 6.63)
Buddhism is not fatalism because it says instead of regretting the past or holding remorse, you should instead cultivate the shame and fear of wrongdoing to instill the mindset of virtue. It says you should not cling to the remorse and regret, because it will harm your mind. (AN 3.99)
Your intentions today can change the present and the future. (Dhp 116 - 122)
But to have the right intentions, you need to learn, think and contemplate. To do this, you need some intelligence. ("They’re wise, bright, and clever" - AN 6.87)
You don't have to be as intelligent as Nobel prize winning physicists, but you need some minimum intelligence (from your old karma), for this purpose. The very fact that you are asking this question shows that you have that minimum intelligence, in my opinion.
Hasten to do good; restrain your mind from evil. He who is slow in doing good, his mind delights in evil.
Should a person commit evil, let him not do it again and again. Let him not find pleasure therein, for painful is the accumulation of
evil.
Should a person do good, let him do it again and again. Let him find pleasure therein, for blissful is the accumulation of good.
It may be well with the evil-doer as long as the evil ripens not. But when it does ripen, then the evil-doer sees (the painful results
of) his evil deeds.
It may be ill with the doer of good as long as the good ripens not. But when it does ripen, then the doer of good sees (the pleasant
results of) his good deeds.
Think not lightly of evil, saying, "It will not come to me." Drop by drop is the water pot filled. Likewise, the fool, gathering it
little by little, fills himself with evil.
Think not lightly of good, saying, "It will not come to me." Drop by drop is the water pot filled. Likewise, the wise man, gathering it
little by little, fills himself with good.
Just as a trader with a small escort and great wealth would avoid a perilous route, or just as one desiring to live avoids poison, even
so should one shun evil.
If on the hand there is no wound, one may carry even poison in it. Poison does not affect one who is free from wounds. For him who
does no evil, there is no ill.
Like fine dust thrown against the wind, evil falls back upon that fool who offends an inoffensive, pure and guiltless man.
Dhammapada