If we did not know the first day of Ramadan month, and we intended to perform fast for what were required [mā fī al-dhimmah], and during the day we came to know that it is actually the first day of Ramadan (before the noon or after that) and we changed our intention, should we later make up fasting for that day? If we did not intend to perform fast but we have not done anything that break the fast and we came to know that it is the first day of Ramadan, what is our responsibility regarding to the fast and qaḍā’ of fast? (Either before the noon or after the noon) If we have done anything that break the fast, should we avoid fast invalidators until maghrib for respecting the blessed Ramadan or we can do fast invalidators?
In the first given case, the qaḍā’ of fast is not necessary because fasting for what were required [mā fī al-dhimmah] is included the fast of Ramadan, even if he came to know after the noon and intended for Ramadan specially, there is no problem to it. In the second given case that you intended for fasting, whenever you came to know that it is the first day of Ramadan, you should avoid fast invalidators, but you should make up that day as qaḍā’, even if you came to know before the noon, as a caution you should make up that day as qaḍā’, and if you did not avoid fast invalidators, upon coming to know the beginning of Ramadan, you should avoid fast invalidators until maghrib and later performs its qaḍā’.