You can add "s" to the end of the verb and not to the person. For example he works, she eats. In that case what you mentioned - for example: I hate him - you will not use the "s" because "him" is not a verb.

Hi Thành, to add "s" or not to a verb depends on the subject of the sentence. So if your sentence starts with He/ She/ It (and it is in the present simple tense), then yes. Meanwhile, "him" is not a subject bạn nhé

Can I add “s” if Verb going with Him ?