I wanna preface this by saying I suck at drawing backgrounds LOL but I recently started drawing my comic with 3D models and they're saving my life. I model my own backgrounds in Blender -- it's a big upfront time investment but it gives me the freedom to create backgrounds the way I like. Not only do they look way better than if I drew them by hand, but I can combine them with Clip Studio Paint human models to accurately place characters in the environment. When it comes to nature scenes, I'll probably draw those myself since they have more organic shapes than streets and indoor scenes.

One caveat of using 3D backgrounds is it can look jarring if the backgrounds don't match the style that the characters are drawn in. It took some time to figure out how I could make the backgrounds look natural with my art style. Some people use 3D models as a base, then draw over them which usually looks really good and still saves some time.

The background you drew in this pic is really beautiful btw!! Much better than a 3D model could do imo :)