If you point a spectrometer at the sky during the day in non-cloudy conditions you will observe readings peaking in the roughly 450-495 nanometers range, which crazily enough, is the definition of the colour blue [0]!

Then you can research Rayleigh scattering, of which consists of a large body of academic research not just confirming that the sky is blue, but also why.

But hey, if you want to claim the sky is red because you feel like it is, go ahead. Most people won't take you seriously just like they don't take similar claims about AI seriously.

[0] https://scied.ucar.edu/image/wavelength-blue-and-red-light-i...

Ever seen a picture of the blue sky from the ISS?

you needed a spectrometer to tell you the sky is blue?