What is a good solution to avoid direct sunlight?

I've heard a lot of people say that direct sunlight is bad.
They say that if your scalp gets hot, it affects hair loss as well.
However, using a parasol is a bit awkward.
The most comfortable thing is a hat.
I heard somewhere that hats are also bad for scalp health.
Furthermore, since my hair is a bit oily and wavy, if it gets pressed down by a hat even slightly, the hair I washed in the morning looks like it hasn't been washed for three days in less than half a day.
What would be a good solution?