
The term 省(province) is the abbreviation of "行中書省" or "行省," meaning a local government directly under the jurisdiction of a central government. Taiwan was a province of China under the Qing Dynasty in the late 19th century and is a province of the Republic of China today. But whether the ROC or the PRC represents the whole of China, Taiwan is a province of China, and that is a sure thing.
However, the diehard Taidu advocates hate the term "province" to the bone, but they dare not erase it by declaring independence. Let them dream the pipe dream if they like to live that way. ( Actually, they cheat the people of Taiwan that way.) Get real, islanders, do not miss the chance of being a "district" like Hong Kong under "One China, Two Systems"; otherwise, you shall take orders directly from the central government in Beijing. Someday.
You may be too young to know the history of "Taiwan Province" since 1949. Kindly see the following report: