Is it permissible for the questioner to fast in the month of Ramadan, given that she was a kidney patient and her doctor prohibited her from fasting when she was 11 years old, and then she sometimes broke her fast after that and did not make up what she missed, and her current age is 18?

All missed fasting days from previous years must be made up. If the exact number is unknown, one should continue fasting until there is a strong presumption that the obligation has been fulfilled. The current Ramadan fast must also be observed if possible, and a doctor's opinion determines the ability to do so. Furthermore, a compensatory expiation (kaffarah) of 750 grams of the staple food of the country must be given to the poor for each day of delayed make-up fasting if the delay was due to knowing its prohibition. No expiation is required if the delay was due to ignorance or forgetfulness.