I've Geo-referenced raster, Is there is any way to extract it's GCP table in QGIS ?
In the Georeferencer tool, there's a button to save the ground control points.
Even if you didn't save the GCP points while the Georeferencer was open, they should be saved "in a separate text file ([filename].points) usually together with the raster image." (source: QGIS Manual)
Eg, I recently georeferenced a raster, and saved it as "Roadmap_modified.tif". Even though I didn't save the GCP points, there's a file called "Roadmap_modified.tif.points" in the same file as the georeferenced raster.