the_content not displaying when using custom fields

I’m editing content-single.php to populate my posts using custom fields. The indivual posts display fine, but when I use the loop to display the posts from that category, the_content does not display. I’m assuming that’s because technically there is no content in the post on the backend: all the contents are dictated using custom fields and the rest is hardcoded in the content-single.php file:

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How can I get the_content data to display outside the single post?