I am an AEIS candidate in Singapore. My father works here with an Ep, but the Immigration Bureau gave me an LTVP strangely, which is a permanent resident parent.

Hello, you can't be a student of LTVP. You'd better apply for a new visitor's pass. If your father is EP, then your mother can apply for DP, but now the children get less DP, mainly depending on your professional entrance examination or performance level.