"South Korea's Constitution limits presidents to a single, five-year term, but Yoon's remark suggests he could accept calls to change the limit to two four-year terms and apply the rule to himself." -Yonhap
(In other words, Yoon wants to change the Constitution so he can rule for 8 years instead of 5).
https://m-en.yna.co.kr/view/AEN20250225001155315?section=national/politics