The pEOArrow consists of solving the arrow while orienting the HKF2L edges. If you know how to do EOLine in ZZ, it should be straightforward. The DF edge and the LL edges do not need to be oriented, so it should be fewer moves than full EO. An intermediate approach would be orienting all of the arrow and HKF2L edges, and then solving the arrow. An advanced way would be to solve the arrow and orient the HKF2L edges simultaneously. The concept of EO is tricky to grasp at first, so I would recommend watching ZZ tutorial videos on YouTube.