Hey Abbey,
Kelowna is... not the best... Options I can think of off-hand are Coquihalla Summit on Highway 5 about halfway to Vancouver, or heading up to Revelstoke and skiing something in that area. There are lots of places you COULD ski along Highway 33 or Highwya 97C (towards Coquihalla but much closer to Kelowna), but not much that's any good. You could possibly look into access out of Apex resort in Penticton, but I'm not sure what you can get into without riding a lift.
Sherman Pass on Highway 20 between Republic and Kettle Falls, WA is pretty good and if you time it right a stopoff at Lost Pass wouldn't hurt, especially if you're after a bit more mellow of terrain. There is backcountry ski access at Mt Spokane too but I have no idea how good it is.
If you go East on Highway 3 there is great ski touring access in the Rossland Range, around Whitewater ski area, and at the summit of Kootenay Pass. Lots of info on this site for those areas. You may want to head back that way and get some Kootenay turns in because it's a massive and massively awesome area for skiing whether it's touring, resort, cat or heli.
The Okanagan is one of those places where you can find good ski terrain, but access is lacking.
I hope that helps at least a bit and that you visit some other places in BC because there are way cooler places than Kelowna lol.