Is it obligatory to make up for the missed fasting days of Ramadan, given that one did not remember at the time that fasting was obligatory, and is unable to make up for an entire month?

If the blood continues for one or two days, it is menstrual blood, and ghusl is required after its cessation. Thus, prayer and fasting become obligatory upon you, and you must make up the days you missed fasting, along with repentance. Making up the fasts can be done during the short winter days. No expiation is incumbent upon you for delaying the make-up fasts as long as you were unaware of the impermissibility of delaying it.