Welcome. Were you born during the brief period when Singapore was part of Malaysia? If so, then try contacting a Malaysian consulate for information. If you were born any other time in Singapore's history, you wouldn't have any special rights in Malaysia, since you weren't born in the country.

In many countries, being born in the country does not give you any right of citizenship. They usuallly require that at least one parent be a citizen at the time of birth. In Japan, for instance, you must have a Japanese father to get citizenship by right of birth.