I live in a pretty hot climate, but it’s only really unbearable at times due to shoddy building and bad urban planning. Even then, summer can be difficult.
I can’t imagine what it’s like on the equator, especially in dense urban centres. What’s Mumbai, Bangkok, or Singapore like at the height of the wet season?! How do millions of people function day to day?
Australian Northern Territory, we have hot humid days every day.
We just sweat and be miserable.
There’s no getting used to it unfortunately just do your best to not get sick from working outside in it