Hello Marcin,
with eIQ Portal there aren't any huge differences in the flow between classification and object detection. The main difference from a user perspective is labeling the various objects (instead of whole images) in the dataset curator. When your dataset is ready, you just need to choose an object detection model and afterwards the workflow is the same.
If you have any specific questions, please create a new standalone thread so that we don't keep reviving this old one. Let's discuss everything in a fresh one with a more specific subject so that it's easier to find for others who look for the same information.
Regards,
David