Can I purposely break a link?

In addition to what has been said to correct an edit that got it wrong: To do a different editing, you can create a virtual copy. You can then start again edititing the asset as a new asset or you continue and do different adjustments to the virtual copy. Lightroom works like a cookbook. It stores the recipe, exporting is like cooking. The cooked meal is like the JPEG files. 

In lightroom, you have one golden rule: never doing file operations outside of lightroom. So once imported, you should use Lightroom for all operation where you would use Windows Explorer or macOS Finder.

(And do not forget to backup both, your image raw files and your Lightroom database.)

Edits that you make on a CR2 (a kind of Raw file) have not committed any change irretrievably. Therefore if there's anything you now don't like or that you originally missed, you can just keep altering the editing further. This can include resetting altogther, or  reversing or updating edits selectively: whether global ones, or local ones (mask based). 

Clearly if you have already printed (or exported a JPG) then after updating this editing you might print again, or export another JPG, showing your latest work. 

OR: say you have two different original CR2s (from two different presses of the shutter button, but otherwise very similar). And you have edited A, but now you wish you had edited B instead.

Having made sure B is also imported alongside A: you can now Sync or else Copy/Paste your work between them: in other words, transfer a copy of all or selected kinds of edit from photo A, onto photo B. There may then be some tweaks needed to e.g. the locations of spot cloning, or to masking (where the underlying content of these two photos does not align). But you won't need to start completely from scratch with this other image.

This approach would be far better IMO, than trying to "switch in" a different Raw file underneath these same edits. Any strategy that depends on 'tricking' the software in some way, has as I see it already started out on the wrong foot. Just use it in a straightforward way, don't overthink, and try to go with its flow - is my recommendation.

If you feel you have made "bad edits" and want to start over from scratch on this photo, simply click the Reset button in the Develop Module. If you only want to undo some edits, use the History panel in the Develop Module to move backwards in time to a set of edits that makes you happier.

Breaking links, moving photo files and "internet links" are all the wrong thing to do, and can make the situation worse.

[Moderator moved from Stock Contributors to Lightroom Classic.]

It sounds like what you're really trying to do is undo the previously applied edits in LRC. You can do that by clicking Reset on the lower right corner in the Develop module. Or you can go to the history panel in the left and step back one edit at a time.

Your question should have been posted to the Lightroom Classic forum. To change the folder in which the image is stored, just drag and drop it from within LRC the new folder. It's important to do this within LRC, or LRC wont know how to find it. Think of LRC as a library catalog card file which knows where every image is located. If you "break that link" LRC won't know where to look. I suggest a good course for learning all the features of LRC. I learned from Ben Willmore on CreativeLive.com