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For a small number of documents (say, a couple of hundred) you can export search results or the contents of a view. This produces a CSV file you can open in Excel. User guide: Exporting Search Results

For a large number of documents (for instance all the content in a vault that has millions of documents) it's recommended to export the data first into a reporting database using the Reporting and Data Export feature and then from there to Excel. User guide: Reporting and Data Export