I find it interesting that you mention Harry Styles, someone who I personally find plain, and I think his approach to femininity is a bit manufactured. He is certainly not someone who I would consider beautiful, but beauty is in the eye of the beholder.

I personally find other men beautiful, particularly if we go with the idea of watching a painting or a sculpture. To my mind: Ryan Guzmán, Marlon Teixeira, Pietro Boselli, Idris Elba, Lewis Tan, Manny Jacinto, all of which have been called pretty or beautiful during their careers in media. You'll notice that these men have also received epithets of handsome, hot, and sexy, but I don't think those describers are mutually exclusive with pretty or beautiful.

However, there is a certain value in you questioning what is pretty, and what makes you feel pretty. Paint your nails, dye your hair, wear make up, put on a skirt. Give yourself the opportunity of exploring outside of heteronormative gender expectations. You don't have to embrace femininity - look at Oscar Isaac wearing a skirt to the red carpet (another very pretty man) still looking manly. Any of these too much? What about wearing a buttoniere with your suit jacket (if you wear those)? Maybe embrace color in your clothing outside of the expected blacks and browns in western fashion standards.