Is it obligatory to make up for the Ramadan fasts of the years in which I reached puberty partially, and the years in which I fasted voluntarily and not obligatorily, with a clarification of the ruling on feeding the poor in each case?

Scholars have differed regarding whether the appearance of pubic hair ( inbat ) indicates puberty, holding various opinions: it does, or it does for a disbeliever but not for a Muslim, or it does not at all.

If the appearance of pubic hair does not indicate puberty, then you are not required to make up any prayers or fasts.

However, if it does indicate puberty, some scholars believe that making them up is not obligatory due to ignorance of the ruling. This is the chosen view of Sheikh al-Islam Ibn Taymiyyah, who argued that divine injunctions are not established until after they have been conveyed, and that Allah does not punish anyone until what the Messenger brought has reached them.

The majority opinion, however, is that it is obligatory to make up any missed prayers and fasts.

As for the days you fasted, believing they were not obligatory due to not having reached puberty, you are not required to make them up, according to Sheikh al-Islam, due to your ignorance of the obligation of intending a fard (obligatory) fast, which stemmed from your ignorance of having reached puberty. The Hanafis hold that whoever fasts Ramadan (definition) with the intention of a voluntary fast, it suffices as an obligatory one. If you were to make up these days as a precaution, there is no harm in it.