Saiyaweess16
I don’t understand your question, as there’s only one reasonable route (= itinerary) between Geneva and Montreux, which is the usual one along the northern coast of Lake Geneva.
What you probably see are the different (usually hourly) connections and their names such as IR90, IC1 or RE33 etc. Don’t bother too much with those, simply focus on their departure times, the trip length or whether a transfer in Lausanne or Vevey is required or not.