Need help for Jungfrau plan

Hi,
I read a post from the member here about 1 day trip which sound great as following
Travel up to the Jungfrau via Grindelwald by train; Go down via Wengen to Lauterbrunnen by train; Walk to Stechelberg via the flat valley floor, or take the bus; Take the cable car up to Mürren; Walk to the other end of the village (20 min.) and either walk to Grütschalp or take the train; Take the cable car down to Lauterbrunnen; Take the train to Interlaken.
I have question about how many hours it take for this plan (estimate). If we leave Interlaken around 8.30 and spend 1.5 hr on Jungfraujoch.
Thks

Hi Sonya! This trip will take about one day and you'll be able to get back to Interlaken by (late) dinner time. It's a great way to see a lot of this splendid region in only one day, especially if weather is clear. Details on the train and bus trips in between can be found through the timetable. Personally I'd prefer to leave a bit earlier for the Jungfraujoch by the way, as weather tends to be better in the early morning. You can best keep an eye on local weather forecasts and decide which train to take shortly in advance. Have a great trip!

Thank you very much Annika.
After we looked at the trail my husband is not sure he can do it. He had knee surgery before.
Are there any nice short walk trail (40 mins max) on flat level around the area on the way to Jungfrajoch?

We would love to see villages, flowers, and mountains as the same scenery of Murren route. Prefer the place that we can hop in and out to the train or cable cart easy.
Can you please recommend?
Thank you very much.

Hello Sonya,

You could consider taking the bus from Lauterbrunnen to Stechelberg and hike back as long as you can, and then get in the bus back to Lauterbrunnen. If possible it would be nice if you could cross the meadows to get to the other side of the Lauterbrunnen Valley, so that you can get close to the Staubbach Falls.
And maybe these hiking tips can give you an idea of the possibilities.

I hope this helps. Have a nice trip,