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Which institutions did Poland and Lithuania share in the Polish-Lithuanian Commonwealth?

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Map showing Poland's territory in 1634 under the reign of Wladyslaw IV Vasa, shaded in pink and spanning from the Baltic Sea in the north to near Kyiv in the southeast. Major present-day cities such as Warsaw, Krakow, Gdansk, Vilnius, Minsk, Lwow (Lviv), Pinsk, and Kyiv are marked within the territory, with surrounding cities like Moscow, Riga, Vienna, and Budapest shown for reference. — Polish-Lithuanian Commonwealth Poland's territory in 1634, during the reign of Władysław IV Vasa.

Under the Union of Lublin in 1569, the Polish-Lithuanian Commonwealth was established as a federated state that shared specific central institutions while maintaining a dual structure.12

The primary institutions shared by Poland and Lithuania included:

Joint Sovereign: The two nations were ruled by a single monarch, who was jointly selected by both parties.12
Joint Diet (Sejm): The Commonwealth utilized a common legislature where representatives from both countries participated to deliberate on state affairs.12
Foreign Policy: The two nations agreed to cooperate and act in unison regarding their international relations.1

Despite these shared institutions, the Commonwealth functioned as a dual state. Formally, Poland and Lithuania remained distinct, equal components of the federation, each retaining its own separate army, treasury, civil administration, and legal codes. All dependencies and colonies acquired by the state were considered to belong to both Poland and Lithuania in common.123