Is buying Ramadan baskets considered zakat, sadaqah, or feeding the poor? And is it permissible to count them as expiation for missed days of Ramadan? And how is that calculated if it is considered feeding the poor?

As for zakat al-mal (charity on wealth) given in a Ramadan basket, it is only permissible according to the Hanafi school, provided it is given to the poor. The majority of scholars hold that zakat must be given in money, which is more cautious.

As for the days you missed fasting and did not make up, making them up is obligatory upon you. Feeding the poor in lieu of making them up is not sufficient. In addition to making them up, you must feed one needy person for each day you delayed making up the fast without a valid excuse until the next Ramadan began. The Ramadan basket is sufficient as an expiation for delaying the make-up fast if it contains the required amount and is given to a deserving recipient.

The required amount for the expiation is a matter of scholarly disagreement. The Shafi'is said it is approximately 750 grams of any food item. The Hanbalis said it is one mudd of wheat or half a sa' of other food items, which is approximately 1.5 kilograms. It is permissible to give the expiation for more than one day to a single needy person. Whatever is not permissible as zakat al-fitr is not considered part of the obligatory expiation.