Is the marriage contract considered valid if concluded at home by the marriage official (Ma`zon)?
Yes, it is valid as long as it is registered at the court.
What is the ruling on giving my mother a gift at "Mother's day", is it Halal or Haram?
Praise be to Allah the Lord of the Worlds.
There is nothing wrong with doing that as long as it isn`t done in imitation of the disbelievers. And Allah The Almighty Knows Best.
Is it permissible for one to give the Zakah (obligatory charity) to his indebted brother?
It is permissible for one to give the Zakah to his brother if he was indebted, or poor.
My eyebrows are very thick. Is it allowed to reduce them by cutting?
All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
It is allowed to reduce thick eyebrows by cutting them, however, it isn`t allowed to pluck or make very thin. And Allah The Almighty Knows Best.