Due to bios limitations the max upgrade for the R7 that is still available is an 8700k (the top is 8086k but it is no longer sold). For this, you need liquid cooling.  Most people who convert use the corsair h60 with a corsair ml120 pro fan.  Depending on your gpu you should look into at least an 850w psu (to run pretty much any non-SLI single gpu).  Like an evga g5 gold 850 for example.  Or seasonic focus.
I am looking to upgrade my pc with a new cpu, I have already upgraded the ram from 1x8gb to 2x8gb 2666mhz and was pleased with the results. The GPU is fine for most games I play but I feel that a lot of games I play would benefit from a new CPU.My current CPU is an intel i5-8400 which is the original , I want to buy a newer more powerful CPU but I need recommendations for which one, my concerns when looking for one are if the power supply is going to be good enough, if it will fit in the motherboard and if it will have sufficient cooling.I have not upgraded the power supply or cooling since buying the tower. I could afford to pay a few hundred for the CPU. Should I get a CPU that will be fine in the current setup or should I also get new cooling and power supply to support a more powerful CPU? Any recommendations or tips would be much appreciated, thanks! - Logan 
Aurora R7, upgrade from i5-8400 CPU