The portrait has been cropped by selecting and masking the image. After that, a posterize and Hue/Saturation mask has been applied. The hat has been distorted for better blending. Later on more images have been implemented like smoke, bullet holes and a few text layer. The benefit of these masks is that they are none destructive and the originals are not modified.
Adobe Photoshop CC is used as the main tool with CC0 stock photos. The portrait is taken by a Canon EOS 3000D which is an entry-level camera.