Sorry...your recording is so muddy I can barely make out your speech at all, much less understand or evaluate it.
Your writing is good, anyway, and there's much to be said for that. ;-{)

Be aware that Japan generally has higher standards for teachers than are required in other East Asian countries, such as China. You'll definitely need a college degree. And being a non-native speaker, you'll likely need a CELTA or other recognized certification (NOT just a garden-variety "TESOL certificate") showing that you are indeed qualified to teach English. The managers at Japanese English schools may not be able to themselves evaluate your spoken English...but they'll definitely know how to evaluate a resume.