Yes .

It's okay. But u should do it lifetime

I keep him in cooler in afternoon and in night . In between he is in fan only! Is there ay problem to keep him in between time in fan

We can’t change the weather, but we can make things easier on our pups. So it is absolutely fine that we can keep our pup in cooler, During the hotter months, it’s important to think about whether your dog is happy, healthy and comfortable....Cooler is the good medium to taking care of our pup. (A Labrador normal body temperature can range from 101 to 102.5 degrees Fahrenheit, which is quite a bit hotter than the average human body temperature (97.6 to 99.6 F)...)

I wouldn't say just only a cooler, but a well managed cooling system for a room, try to place it on windows outside because you're gonna have to keep it always on because of puppy

Yes

Ok