Estonian spelling is consistent, i.e. the same letter always stands for the same sound. One exception is palatalization, which is not denoted by any letters or symbols you have to know when to palatalate. This takes practice. Listen to the native speaking audio for practice.
A second exception is long sound length. There are no symbols for distinguishing between long and overlong. Both are spelled with double letters, and again - you have to know (= conclude from the context) which is which.