The fields on the Asset Summary page cannot be changed, and some fields will not be displayed if they do not contain any data (they are available in edit mode, though). You can add extra custom fields to the Asset Summary page, as explained here:
Configure and add data to asset custom fields
Similarly, the default Assets tab does not allow direct customization of visible fields. However, you can achieve this flexibility by creating a custom report. To get started, we recommend using the built-in report "Assets: All columns from the Assets menu" as a foundation. You can then modify it to display exactly the fields you need.
Use our database dictionary, which explains in detail what each database table and field stores. More information on the dictionary can be found here: https://www.lansweeper.com/knowledgebase/accessing-the-lansweeper-database-documentation/