The Kettle Valley Railroad bed near Kelowna is a great place to walk or ride a mountain bike. Very scenic. Gorgeous in October, but you'll be too soon for the fall foliage obviously.
There are some interesting pictures to be had in the southern part of the valley, e.g. on the Inkameep Indian reservation. Lots of roads wandering around.
I haven't lived there in 20 years so I don't know what restaurants I'd recommend.
Kokanee beer is brewed nearby - if you've not had it, you should try some.
There have been major issues with forest fires the past few years. If fire-damaged forests seem interesting to you (in black and white they might be great subjects), they are all around, especially near Kelowna. A major fire hit Kelowna a few years ago. Another one is currently burning in West Kelowna, across the lake.