During the encounter, Kelly was able to ask one question; what is the hardest thing that humans are going to have to adapt to, to reach our climate change goal?
The answer was "different, but it made sense", she said.
"He said women empowerment, which was really cool and he talked about how women bring sincerity that men sometimes lack and also the drive to get things done quickly and just less talk and more action."
Guterres' "humble" nature reminded Kelly a lot of her grandad who passed away last year.
"My grandad was a businessman. He was very respectful and knew what he was talking about, but he was very approachable and the UN Secretary General was just the same; you could ask him any questions.
"He was just a very nice man and he had a bit of humour to him and straight to the point as well."
Having been given the opportunity, Kelly believes similar experiences should be available for students.
"There should be more things for youth to be involved in. Because for me, after I did the Blake Inspire programme, it gave me more confidence and led to this opportunity."