failed my emissions need help with the codes and what i need. i already kno i need a new cat.

here's the test results..

RPM=0757
KOEO = PASS
READINESS = PASS
MIL CMD = FAIL
CODES READ = 1
DLC = PASS

DTC1 = P0420 Catalyst Sys Efficiency Below Threshold (Bank 1)
DTC2 =
DTC3 =
DTC4 =
DTC5 =

Fuel Cap 1 Test = Pass
Fuel Cap 2 Test = None

Catalytic converter = Present