You can resize the widget any time, both when adding it and after it's already added to the Home screen. To learn how to do it when adding a widget, consult this article.
If you want to adjust the size of an already added widget, tap and hold the required widget and then drag the border frame around it up/down and left/right to resize it. When finished, tap on an empty space on the screen to exit the edit mode.
Relevant for Android versions 9.0 and higher.
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