To create a basic report that lists all (active) assets, open the report builder under Reports\Create New Report, give the default report that is generated a title and hit Save & Run. For software, there are some built-in reports in the Reports tab.
Lansweeper uses a SQL database and a standard SQL editor for its report building. It's not possible to list everything in the database in a single report. The database contains dozens of unrelated database tables. Including all of these tables in a single report would lead to endless rows of duplicates, due to the way SQL works.