Dtc’s code 2539,and p205c What is this

Hello, nothing to purchase based on codes alone. Diagnostic testing is needed. Those codes may or may not be related. One relates to fuel pressure delivery as measured, and the other to something called "reductant tank temperature". I'm guessing you have a Diesel engine equipped vehicle with a Diesel Particulate Filter system. There is no easy guesses here; testing by someone with experience and skill with this vehicle is needed. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops