Yes, you need to make it clear when you agree with something. And its simple in Chinese too. It can be translated as ''对", which is pronounced as 'duì '.

When you say the word 'duì' , you need to stress the fourth tone, loud and proud :)

Once you master the word for Yes, its half to the word for No. No can be translated as '不对'.

不 (bú), second tone, means no, not,
对 (duì) means right, or correct,
so together 不对 (bú duì ) means not right, not correct.