Is there a light rail from Huizhou South Station to Huicheng District?

No, according to the information of Huizhou subway, there is no subway from Huizhou South Station to Huicheng District. You can take a bus from Huizhou South Station to Huicheng District, and there is no subway from Huizhou South Station to Huicheng District. Light rail is essentially a subway system, which uses the same standard track as the subway and even the national railway. The official definition in China is that the C-type subway train is called light rail train, that is, light rail train is essentially a kind of subway train.