do someone good, means to be good or beneficial for someone. 中文意思也就是：对......有益/有好处；

几种表达句型：

It will do me good to go on a holiday. 去度假一下对我很有好处的。

Will this workout do me any good? 这样健身对我有没有什么益处啊？

A nice hot bath really do you good.