What should I do about the days I broke my fast in Ramadan due to masturbating, and should I fast the days I missed from the age of seventeen or from when I started masturbating at the age of sixteen, knowing that I was unaware of its ruling during some periods?

There is no doubt about the prohibition of masturbation, and one must repent from it. If you engaged in it out of ignorance of its prohibition, then there is no make-up or expiation upon you. But if you were aware of its prohibition yet ignorant that it invalidates the fast, then you must make up the days during which you invalidated your fast. However, if you are unsure about when you learned the ruling, the default is ignorance, and there is nothing upon you.