The Prophet, may Allah bless him and grant him peace, conveyed it to the Muslim community, and Muslims hear it from one another. This is not like Moses hearing Allah’s speech, for he heard it without an intermediary. What Muslims recite and write in their copies of the Quran is Allah’s speech, not the speech of anyone else. They recite it with their own voices and write it with their own ink on their own paper. Their actions, voices, and ink are created.
The Quran they recite and write is the uncreated speech of Allah Most High, whether or not they are rewarded for their recitation, and whether they write it with vowel marks and consonant dots or without them. This does not alter the fact that what is written is the Quran—the speech of Allah which He sent down to Muhammad. What is between the two covers is Allah’s speech, whether it has vowel marks and consonant dots or not. Allah’s speech is sent down and uncreated, while the voices of His servants and the ink are created.
The Arabic Quran is Allah’s speech, which He Himself spoke. It is not that part of it is Allah’s speech and part of it is not. Neither Gabriel nor Muhammad had any role in it other than conveying it; neither of them originated any of its letters. Rather, all of it is the speech of Allah, Blessed and Most High.
These “questions” are discussed at length elsewhere, beyond this answer. This, however, is as much as this sheet could accommodate. And Allah knows best.