Check engine light on after repair, codes PO300, PO300 and PO171

Hello, I'm Danny
The code P0300 Was for a random/multiple misfire that sounds like was fixed when you changed the plugs and coils, But, The Code P0171 is for a Bank 1 system too lean. That usually means there is a vacuum leak or and alternate way that air is leaking into the engine and being burned during the combustion process.I've attached pictures below as a step-by-step guide to help diagnose the problem. Hope this helps and thanks for using 2CarPros.
Danny-

Thank you for the reply. Many people just leave without saying if they were able to repair the issue or if anything. Please return anytime with your automotive related questions.