I don’t know about highlighting the actual text (maybe you want to do this to copy it), but if you just need to get that info into the clipboard then that is easily doable using RegEx.
Basically it’s a matter of getting the webpage’s contents into the clipboard (can be done using a simple JavaScript and other ways too), and then using RegEx to search for the string between those two words and saving that string to the clipboard.
Anyway you could post a link to the page you’re working with so we can provide some more help?
Edit: just saw that this is your first post! Welcome! This is a great community with lots of knowledgeable people who are always glad to help. If you haven’t had the opportunity to do so already, check out this article that talks about the best way to get the quickest answer to your questions.