If you wish to store the message as an external resource you will need to use string.Format rather than string interpolation, interpolated strings have to exist in their entirety at compile time as string literals.
You will also need to ensure that the number of variables contained in the message match those in the code calling string.format otherwise it will not transpose correctly.
As an example, this is using a resource file;
var message = string.Format(Strings.ErrorMessage, value1, value2);
Strings.ErrorMessage would contain;
"This is the error {0} and message {1}"