I’m confused by this though (of course it’s from wikipedia so it may be inaccurate) …
Congress may not strip the U.S. Supreme Court of jurisdiction over those cases that fall under the Court’s original jurisdiction defined in the U.S. Constitution, and instead Congress can only limit the appellate jurisdiction of the Court.[8] According to the Constitution, the Supreme Court has original jurisdiction in, “all Cases affecting Ambassadors, other public Ministers and Consuls, and those in which a State shall be Party…” This last state-shall-be-a-party language does not mean that the U.S. Supreme Court has original jurisdiction merely because a state is a plaintiff or defendant, even if a provision of the U.S. Constitution is at issue; instead, the controversy must be between two or more states, or between a state and citizens of another state, or between a state and foreigners.[9][10] **Additionally, in 1892, the Court decided that it has original jurisdiction in cases between a state and the United States.[**11]
What part confuses you? The second sentence is a quote from the Constitution. The Constitution does not confer jurisdiction in the case of a plaintiff suing his own state, but if a state is a party under the other provisions, then SCOTUS has original jurisdiction.