"제가 친구를 도와주는 것을 좋아해요."
Translation:I like helping my friends.
Naturally when I think of friends in general I would say I like helping any or all of them, so I assume friend is plural. If I wanted to specify a particular friend, I might use the topic marker <sub>은/</sub>는, thereby putting emphasis on a particular friend.
Korean is vague like this, and context has to supply the rest of the story, where cultural assumptions can mean a lot in the spoken language, more than in American English.
Could anyone clarify how "helping" works as a gerund here, because the noun functional aspect of "helping" is not coming across. Perhaps this is where it works as a gerund in Korean but it's untranslatable as such in Eng?
It helps to replace the gerund part with "it". If you can replace the phrase with "it" then you know it is a gerund. e.g. I like "helping my friends" can become I like "it". So helping is a gerund here.
Actually "I" or "제가" is the subject, because the action of liking is performed by "I" or "제가". "Helping" or "도와주는" is still a gerund, simply as the object of "like" or "좋아해요". But yeah, the tip of replacing the gerund with a pronoun works really for checking if it actually is a pronoun.
I thought it wasn't at first, but it is - "helping friends" is the subject of the verb "like".
The 를 on 친구를 denotes the 친구 as the object of the sentence, i.e. the thing that is being helped.
Your sentence would be 재 친구는 도와주는 것을 좋아해요