:salam2:
Brother, we don't pay zakat on our earnings but on Savings.
The day your saving reaches nisaab level(value of 85 gms of gold. It was approximately 700-800$ last year) you should start counting days. Once it reaches 354 days(acc. tp lunar year) and you still have the balance above nisaab level you should pay zakat on your savings and assets totally.. (We don't pay zakat on the things we use for living. for e.g house, car, etc..)
Remember if you are earning million dollars per year and you are not saving to nisaab level, you are not obliged to pay zakat.
Regarding to whom we can give zakat(obligatory charity), Allah s.w.t mentions about this in Surah, Al-Tawba in aayat 60. The translation is
"The alms are only for the poor and the needy, and those who collect them, and those whose hearts are to be reconciled, and to free the captives and the debtors, and for the cause of Allah, and (for) the wayfarer; a duty imposed by Allah. Allah is Knower, Wise."
So..You can pay zakat to only above 8 categories. Among these categories you can give it to those who need or deserve more..
You cannot pay zakat to your parents, grand parents (all above in the hierarchy), children, grand children(all below in the hierarchy), wife, prophet family. [may be some more, but i don't remember now..]
May Allah accept all our zakat and sadaqas.