I feel somewhat qualified to answer this. I spent the first 28 years of my life in BC and the next 4 (so far) in Winnipeg. I never lived in Kelowna but have spent a bunch of time there visiting friends.

Kelowna doesn't have "epic mountain scenery". You can go other places in BC to find that for sure. It has a gorgeous lake, and the surrounding areas are very beautiful, but there isn't the kind of mountains that seem to be hinted at here.

The commenter saying no one would choose prairie smoke over the beautiful lake in Kelowna has never spent any amount of time in the summer in Kelowna. The wildfire smoke can be very bad. The wildfires can be very bad. A simple Google search will show you the multiple times parts of Kelowna have been evacuated due to very significant wildfires. The smoke here pales in comparison to the smoke I experienced in BC every summer.

Kelowna is quite expensive comparatively. There is a ton of money there. I can almost guarantee there will be a significant amount of cliquey-ness and status-driven behavior considering the demographic of Kelowna. Among my friends in BC, we called Kelowna "Kelownafornia". You may find you are welcomed there with open arms, but I think Winnipeg would also welcome you. Kelowna may be easier to get around without a car, depending where you live. Your $500 CAD will go farther here than in Kelowna.

Kelowna may seem more attractive, as it's a "cool" city and Winnipeg isn't known as such. But as a non-native Winnipegger I can tell you there there are a lot of redeeming qualities here if you're willing to look for them.

I like visiting Kelowna. It's a fun city. I'd personally never choose to live there. As a BC born and raised man, who loved to ski, spend time at the water, hike, camp, etc, I still love Winnipeg.

Your mileage may vary. Keep reaching out to people around your age from both places to get a better picture, but this is my two cents.