Complex sentence: Making her senior Grand Prix debut, she finished 5th at the 2017 Rostelecom Cup before winning silver at the 2017 Skate America with new personal best scores for both the short program and free skate.
Split into simpler sentences: Making her senior Grand Prix debut, she finished 5th at the 2017 Rostelecom Cup. She then won silver at 2017 Skate America with new personal best scores for both the short program and free skate.