There isn’t any tool that I know of that will create dummy acf data. This one is good, but you need to create filters to insert content for ACF fields https://github.com/bordoni/fakerpress which means you’ve already gotta know how ACF stores data for each field.
Each field stores data in a different way, not all fields are special but it would still take pages to explain in all. Most fields simply store text values of the input.
I would say to create at least one post with the fields and then search the postmeta table for that post ID to see how it’s stored. Then if you don’t understand what you’re seeing for a specific field type to let me know and I’ll explain it.
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