A: 인도네시아 음식이 정말 매워요. B: (그것은) 한식보다 매워요? B means "Is it spicier than Korean food?" It denotes "Indonesian food" So, it means a "Is Indonesian food spicier than Korean food?" As you know, 한식보다 인도네시아 음식이 매워요 means "Korean food is spicier than Indonesian food". But, there is no reason that the above question should mean "Is Korean food spicier than Indonesian food?". The speaker asked whether the Indonesian food is spicier than Korean food or not.

I guess it is 한식 not 학식. 학식 means school meal if I'm not mistaken. If so, it means "is it spicier than Korean food?"