difference between 言った and 言われた

言った is the past form of 言う and, as you said, it means "said" or "told".

言われる is the passive form of 言う and it means "to be told". 言われた is the past form of the passive, and so means "was told".

彼は医者に禁酒するようにいわれた。

He was told to abstain from drinking by the doctor.

勉強をするそうに　いわれた