How to make Safari use the List view not the Column view
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On macOS Big Sur, click the button shown on the screenshot and pick another view.

These are the options shown to me:

Ícones = Icons
Lista = List
Colunas = Columns

Edit: alternatively, when you have the window open, you can use the same shortcuts that are also available on Finder: [command] + [1], [command] + [2], [command] + [3] to pick the respective options, as Tetsujin mentioned.