Tutorial: embedding reports in Delphi
Integrating the report in Delphi
To integrate the report in Delphi you must install first the correct packages, refer to documentation in Delphi (and Kylix for legacy builds).
New components appear in the palette (reportman section) wherefrom most important is the VCL report component (the legacy CLX builds used TCLXReport).

To pass custom opened datasets (any dataaccess engine with a TDataset descendant like Zeos, Direct Oracle Access...) to the reporting engine you can use the AliasList property on the report component and a TRpAlias component that establishes relations between aliases and Application datasets.
Drop the report component to a form and select a report by clicking the button beside the Filename property. You can select also the preview property and the title.
Place a button and call the execute method at onclick event as this:

If you have problems compiling the application check the library path includes the path to the directory where reportman packages are stored.
You can call other methods like SaveToPdf, ShowParams...