>> Day1 - arrive in Zurich around 1pm
Trip to Rhine falls, stay overnight in Zurich.
Zürich and the Rhine Falls are pleasant, but there are many places more worthy of your time, especially if this is your first visit to Switzerland. Consider going straight to Luzern/Lucerne and spending 2 or 3 nights there.
There is information about these places on the following pages:
>> Day2 - leave for Interlaken leave in morning. Do some sightseeing and some activities. Need suggestions in and around Interlaken would want to keep it low for this day.
By "low", do you mean "low altitude"?
Interlaken itself has little to offer. If you don't want to visit somewhere like Mürren (altitude 1,638 metres) or Schynige Platte (altitude 2,076 metres), you could go for a cruise on the Brienzersee (Lake Brienz) or the Thunersee (Lake Thun). What you can do will depend on what time you arrive in Interlaken.
>> Day3 - trip to jungfrauzou
It's called Jungfraujoch.
>> Day 4 - trip to my titlis
This trip would be best done from Luzern to avoid excessive travel times.
>> Day 5 - not sure on this day, maybe Zermatt or maybe a day trip on glacier Express or Bernina Express
Zermatt is around 2.5 hours each way from Interlaken, so that's 5 hours travel, plus whatever time you spend in Zermatt.
The Glacier Express does not start, finish or pass near Interlaken, and the whole route takes around 8 hours. You could do the sector from Brig to Zermatt if you don't mind the travel time. Reservations are compulsory on the official Glacier Express train, but you can travel the same route on normal trains with no reservation.
The Bernina Express route is on the other side of Switzerland, and is not feasible as a day trip from Interlaken.
You could consider taking the Golden Pass train from Interlaken to Montreux (around 3 hours each way).
>> Day 6 - back to Zurich in the day and do some shopping and sightseeing. Any ideas around Zurich or on the way from Interlaken to Zurich? Overnight in Zurich, fly out early morning day 7.
If you have not been to Luzern, it would be worth breaking your journey at Luzern for a few hours, to walk around the old town and see the Chapel Bridge, all of which is close to the station.
In Zürich, you could walk through the old town on both sides of the river. Other ideas are here:
I hope this helps you to clarify what you would like to do in the time you have available. Please don't hesitate to ask further questions as your planning progresses!