If you want to work with data (like from a database) instead of block-content (which are data items assigned to one instance) you need to get it from somewhere and then loop through it. Typical data comes from:

• the current App, using App.Data[...]
• a query in the App, using Kit.Data.GetQuery(...)
• a SQL database - either through an App Query, from a DataSource or from a SqlReader
• a CSV file - either through an App Query, from a DataSource or from your own code
• DNN objects like the users - either through an App Query, from a DataSource, from DNN-objects or from your own code
• a JSON or XML file - usually loaded from your own code
• a WebService - usually loaded from your own code

Once you have the data, you will usually want to loop-and-show, which is easiest using dynamic objects, so you can just type things like @Content.FirstName to show the properties.