[Kelsey]

Where should I put the PHP to show custom fields on my posts? Which PHP file should this go in?

[Theme Horse Support Team]

Hi Kelsey
Where ever you keep the custom fields all your data will be lost while upgrading our theme. So better create the child theme and add add_meta_boxes() under child theme.
Learn more about child theme

https://codex.wordpress.org/Child_Themes

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