Hey, @ryanhoward79. Thanks for reaching out about this!
There’s a tutorial here in the Community for adding customization information on product pages. It provides the coding and steps to include various additional customization options on your product page. As well, it goes over how to prevent customers from adding a product to the cart before they have completed the required information.
Since this type of customization is unsupported by our Theme department, I recommend reaching out to a Shopify Expert if you need a hand with it. Take a look at the Help Doc for the Experts Marketplace to learn more.
Hope this helps!
Where are you adding custom fields? Product page? Cart page?
Depending on your use case, it may be simpler (for you and you customers) to collect that additional information during registration and require customer accounts.
Why is this feature not offered and supported by Shopify? It seems many sellers would like the option to provide a custom field for products, and the third party apps charge a monthly fee for this. This is a simple addition to the variants. Is there a reason it's not supported for those of us with no coding experience?
The feature is offered and supported by Shopify - through their cart item properties among other methods. It's up to theme developers whether or not to offer these kinds of features in their themes. If your theme does not support custom fields, it's easy enough to add them to the theme's product form, using something like this:
<input type="text" name="properties[Enter your desired property name here]"/>
This will be carried through to the orders admin page.
Hope that helps!