We need to highlight a specific field within a 'Field Editor'. Please let me know how we can do that

This sounds like a job for custom javascript. Could you provide any more detail into what you’re wanting to do?

Thank you for your reply.
I have added a screenshot below. In this field editor I need to highlight “New”, so that user can find it easily.

Please let me know what should we do.

You’d have to find the specific location of the code in the console, then apply a custom css In-Line

Here is the tutorial on how to apply CSS