Can I start fasting based on the moon sighting of another country?
You must follow the moon sighting of the country you are in.
What are the Sunnah acts of fasting?
● Delaying Suhoor (pre-dawn meal) as long as there is no risk of Fajr beginning.
● Hastening Iftar (breaking the fast) immediately after confirming sunset.
● Performing I‘tikaf, especially during the last ten nights of Ramadan.
● Reciting the Quran frequently.
● Avoiding idle and useless talk.
● Being generous and charitable.
● Guarding oneself from desires.
● Purifying oneself from major impurity (janabah) before Fajr.
Is the son of the sister by breastfeeding considered a mahram in Islam, and is it permissible for a woman to go for Hajj with him?
Everything that is prohibited by lineage is also prohibited by breastfeeding. The son of the sister by breastfeeding is considered a mahram, just like the son of the sister by blood, and it is permissible for him to be her mahram for Hajj and Umrah. And Allah Knows Best.
Is it permissible for a mother to stop her daughter from marrying a respectable, God-fearing young man because he isn't college/university graduate?
It is impermissible to deny a woman her right in getting married except for a lawful reason, and problems can be solved through dialogue. However, she can file a suit in order for the judge to have a say in that regard.