https://en.wikipedia.org/wiki/Hanja
> South Korean primary schools abandoned the teaching of Hanja in 1971, although they are still taught as part of the mandatory curriculum in grade 6. They are taught in separate courses in South Korean high schools, separately from the normal Korean-language curriculum. Formal Hanja education begins in grade 7 (junior high school) and continues until graduation from senior high school in grade 12. A total of 1,800 Hanja are taught: 900 for junior high, and 900 for senior high (starting in grade 10).
https://en.wikipedia.org/wiki/Comparison_of_Japanese_and_Kor...
> Japanese and Korean both have an agglutinative morphology in which verbs may function as prefixes[13] and a subject–object–verb (SOV) typology.[14][15][16] They are both topic-prominent, null-subject languages. Both languages rely heavily on turning nouns into verbs utilizing "to do" (する and 하다).
> Modern Korean and Japanese share a similar system of demonstrative pronouns: i- (이), ku- (그) and ce- (저) for Korean corresponding to the Japanese ko- (こ), so- (そ) and a- (あ)(“this”, “that” and “that over there”). They both lack a compulsory distinction of plurality (for example "an apple" vs "apples" is usually not specifically distinguished).
While in many countries, people start learning English when they are in elementary schools. Upon until getting out of college, that is some decent years spent on English alone.
While the language itself is significantly different, more reading and extension of vocabulary should the few pending items to master English from that point on.