Can daily moderate bicycling for an hour everyday improve skin quality?

YES, many benefits: Aerobic exercise like bicycling has many health benefits, including improving the health of our skin. I also advise a healthy diet with lots of organic vegetable and fruits and healthy oils and a quality multivitamin. See https://www.totaldermatology.com/exercise-for-healthy-skin-the-unknown-benefits-of-being-active/

I would say no-: -exposure to the sun causes skin damage, unless you be sure to use sun block. But cycling by itself has no effect on your skin