How many categories and what quantity in kilograms of Zakat al-Fitr must be distributed, and to how many needy people? Is it permissible to distribute it outside the country if there are no poor people [in one's own country]?

The variety of categories for zakat al-fitr does not mean that one must give from every category. Rather, what is obligatory is to give it from the staple food of the people, such as rice or wheat. Its مقدار (amount) is one sa' of food (approximately 3 kilograms of rice), and it is given on behalf of oneself and those one is obliged to support, provided there is an surplus beyond their sustenance. It is permissible to distribute a single fitr (zakat payment) to more than one needy person, just as it is permissible to give several fitrs to one poor person. The general rule is that zakat should be paid to the poor of the country where the person resides, and it is permissible to transfer it to another country if there are no eligible recipients [in the former].