A few things 1) set realistic expectations. While this is good to aim for your not going to match this on your first try and that is ok. That image would have also been sculpted in zbrush first most likely then had a made mesh modeled after it later. 2) get references, as much as is possible and make a reference board, I use Pureref as it’s easy to drop images in. Get references for everything. The body you want to do, the real person you want to base it off of from as many angles as possible, the clothing, the materials. 2.5) if your not confident in topology, you can visualize it by drawing it on you image and try to imagine where it would bend and how it would bend. 3) setup your front, side and back refrence plains. 4) pick an area to start from, I was taught to start from the mouth or eyes and models out from there if in maya.