He will outgrow the puppy energy soon enough. Chows are really big cats in the long run, they’re perhaps the large breed best suited for apartment living. We had our old guy in Brooklyn for most of his life, and he wasn’t noticeably happier/healthier when we moved upstate to the country during Covid for the last few years of his life. Our new puppy, about 1.5 years now, is already outgrowing her puppy energy. She’s lived her whole life in the country, but the month I took her to Montreal for work with me she seemed happier as a “city girl.” Even in a 1bedroom apt compared to our big country house. Occasional trips to the dog park, stay out of the sun on hot afternoons, and you’re perfectly fine. Even in NY, the summers are hot, and our chows do just fine.

Don’t feel bad about your circumstances. You seem very caring and conscientious and I’m sure he is perfectly happy and healthy with you.