241 posts
A lot in the time you have available but achievable just the same.
I would definitely take the Zentralbahn train from Luzern to Interlaken Ost.
Plan your day based at Interlaken to do one of the several spectacular mountain adventures or perhaps a cruise on one or both of the lakes.
Others can advise about the most appropriate ticket or pass.
But the resources you need will be on this site or the links from it.
Enjoy your travels!
72625 posts
Hi Biplab das33 and welcome to MySwissAlps!
To know which rail pass is the best for your specific itinerary you need to plan out all trips you will make (train, bus, boat, cable car) and compare the prices for regular tickets to the rail pass price (and which routes/mountains are free or discounted). Once you have that information you can read our page here on how to choose the best rail pass. There is a spreadsheet there to help with the math. 🙂
https://www.myswissalp s.com/train/ticketspas ses/practical/choosera ilpass