Hello Quikacku67 .
Sorry to say this but 1 ½ days is not enough to visit Montreux and Chamonix. Either visit one of the two. Why is not doable? Well look up the train timetable to get an rough idea on the travel time. Daylight is short at this time of the year.
If you want to go to Montreux, you could purchase the Montreux Noel offer:
Montreux Noel offer
For the city of Geneva, if you gonna stay there in a hotel, you will get the Geneva transport card for free travel within the city.
https://www.geneve.com/en/plan-stay/getting-around/free-geneva-transport-card
Kind regards,
Roland