Realistic Retouch of AI Portrait

I have a portrait that was generated with an AI tool, and at first glance it still feels too synthetic. I need your eye for realism to push it over the line so it can pass for a genuine photograph. The core image, including the background, must stay intact—I like the setting exactly as it is... (Budget: $10 - $30 USD, Jobs: Adobe Lightroom, Adobe Photoshop, AI Image Editing, Illustrator, Image Processing, Photo Editing, Photoshop, Photoshop Design)