What is the difference between "I’ve gotten to do" and "I have to do"?
Context:
Hi Mom, Dad, and Sam,
The Vatican is weird! As you can see, the Catholic Church still has a lot of money left over from the Middle Ages. I’ve gotten to see all of the art, including the Sistine Chapel ceiling and sculptures by Michaelangelo, Donatello, and the rest of the Ninja Turtles.
Answer
“I’ve got to do” and “I have to do” are synonyms (or pretty nearly so), meaning roughly “I must do”.
“I’ve gotten to” is a different sense of the verb get. Here have is purely an auxiliary to form a past perfect, the verb get could be used in the present sense: “Today, I get to see the Sistine Chapel”. The meaning is “I have the opportunity to see the Sistine Chapel, and I am taking this opportunity”.
Cambridge British English dictionary reference: get verb (have chance)
In the past tense, there is a potential confusion between “I’ve got(ten) to” in the sense of “I must” and “I’ve got(ten) to” in the sense of “I could”. This ambiguity is resolved differently in British English and American English. In British English, the past participle of get is got. In American English, the past participle of get is usually gotten (though got is also used). In the sense of “I must”:
[BrE] I have got to see the Sistine Chapel.
[AmE] I have to see the Sistine Chapel.
In the sense of “I could”:
[BrE] I got to see the Sistine Chapel.
[AmE] I have gotten to see the Sistine Chapel.
Attribution
Source : Link , Question Author : Igor V. Novokshonov , Answer Author : Gilles ‘SO- stop being evil’