WordPress repository ask yourself this if I wanted to change the design of my site future and installed WordPress theme, would I want this change to remain. it'll default to the catch-all index php file, which is why every standalone theme has to have index php file.. WordPress will use this new template file instead of the one from the theme. You already have template at your service in the form of theme, and all you need to do is to create separate style css file for your child theme, and add the customization tweaks as per your needs.. do not fret WordPress will know to use the files from the theme unless you add new files to the theme that override them. By making copy of the relevant file from the theme, To add customizations, I find it easier to start, adding that to the theme, and then editing it.. So, you've created WordPress not and because you want to add functionality or override one or more of the in the parent theme.. you write another in your child theme with the same name and WordPress will run that function instead of the in the parent theme.. you can write in your child theme that unhooks it from the hook it's attached to.. check that you added the priority and that your spelling is identical to the spelling of the function and the in the parent theme..
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