Complex sentence: After arriving to Parth Galen, Boromir gives in to the Ring's corruption and, seeing it to as a means to save Gondor, tries to take it from Frodo and coming to his sense too late as the hobbit decides to continue the journey alone.
Split into simpler sentences: After arriving to Parth Galen, Boromir gives in to the Ring's corruption and, seeing it to as a means to save Gondor, tries to take it from Frodo. He comes to his senses too late as the hobbit decides to continue the journey alone.