Yes you could paint. The outcome will only be as good as the prep or the paint will peel over time.

You could refinish the existing door. Stain on wood is far more forgiving long term. Y

Entry door kick plates are protective metal or plastic plates installed at the bottom of doors to prevent damage from scuffs, kicks, and pet scratches. Commonly available in brass, stainless steel, aluminum, or matte black, they are installed on the push side of the door. Standard sizes are typically 6 or 8 inches high by 30 to 34 inches wide for a 36-inch door.

Looks like it was replaced at some point as the trim and style does not match the transom window above. I would change it to a simpler single door with 2 sidelites and paint. I would also seriously look into eliminating the radius top transom.

Thanks for your thoughts!