What can be read from OBD II port


Please can you tell me what in general can be read from vehicle which have OBD II port. I’m interesting what is major difference from Carly, as layman (means easy explanation logs) like to read in real time behavior from my car, and as plus want to use yours latest board II generation with LTS support for basic hardware intrusion detection, means want to integrate motion detectors with your device, is it possible, and excuse me if question is basic but like to know, and/or point me with links where can I found information.