The lines you are referring to are the nasojugal folds or the tear troughs. They can be from pigmentation changes to the skin or shadowing or both. In your case, it appears that you have shadowing as the primary cause. Shadowing is from the double convexity of your lower eyelid and cheek with the depression in between. This happens to us all as we age. It can also be exacerbated by things like lack of sleep. The most common way to correct this is to fill the line with something like Restylane or Belotera. This is a quick office procedure and will restore the rested/youthful contour of this area. You can also fill the area with your own body fat which is permanent, but the procedure is a little more involved. Finally, you could opt for lower lid blepharoplasty with fat repositioning. My advice would be to see a qualified surgeon who can guide you through the process. Without the advantage of a physical examination, it appears that you would do well with the simplest option (fillers). Best of luck!