Perhaps the easiest way to tackle this task would be to use *system* strings that have some fixed starting and ending characters, e.g. ##FirstName##, or @@FirstName@@ - or something similar.
You should instruct your users what the list of those *system*strings is, so that they can insert those where needed. Then, on the server side, all you need to do is run some simple String.Replace methods that will replace such a string with the exact database row data.
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