You can link the “Read More” to the “Custom Feild Values” using the Post Grid Combo plugin. This article will help you link the “Post Date” to the Custom Field values.
To begin, insert the “Read More” block.
Click on the “Read More” tab.
Now choose “Custom Field” from “Link to” to link read more to the custom field value.
Add a “custom meta key” to link with the post date.