How do you replace pcv tubing on 2003 Mazda B3000 on 2003 Mazda B3000

Went to shop and was told I need to replace pcv tube. I have a check engine light on. I'm burning a lot of gas. No power after 80 with the pedal to the floor unless I'm going down hill. I'm also getting a code to replace oxygen sensor bank one and two. they have been replaced still getting same code.

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WHAT CODE??