Hi apple, there are very close but there is a difference. Skilled means having lots of training/experience and it is the best word to use when talking about workers and laborers. Skillful means expert at a particular job, but not necessarily because of training or experience( surgeons, artists,footballers, etc)

两者都可表示“熟练的”，但有区别：skilled 主要指因受过专门训练、有丰富的实践经验等，从而掌握了某项专门的技术。而至于后者更多是一种天生的素质，翻译成“灵巧”更适合。