句子结构没错,把just like 改为just as ...does,把many time 改为much time （time是不可数名词）
You should study hard to become a star just as your favorite star does rather than spend much time on him.
翻译：你应该努力学习使自己成为一个明星,像你自己喜欢的明星那样去做,而不是在他的身上浪费太多时间.