This cipher involves shifty letters! Cnebnl Vtxltk bl max uxlm unm fr ykbxgw ebdxl Gtihexhg uxmmxk yhk patmxoxk kxtlhg. Ha pxee. Max yetz bl xtlrvmy{Gti0exhg_ol_Vt3l4k}
You might want to read up on Caesar ciphers.
As the problem suggests, the text was encrypted using a caesar cipher. A quick google search leads us to http://www.xarg.org/tools/caesar-cipher/.
Pasting the ciphertext in and setting the key to guess, we get
Julius Caesar is the best but my friend likes Napoleon better for whatever reason. Oh well. The flag is easyctf{Nap0leon_vs_Ca3s4r}
easyctf{Nap0leon_vs_Ca3s4r}