@jason9harry We’ve identified several concerns in your message and responded to each below:
Do I need to upgrade to the premium edition in order to edit my permalinks?
No. You can edit your site’s permalinks even without the free version of Yoast SEO installed, as this setting is controlled in the general WordPress settings under Settings>Permalinks
Is it possible to switch the permalink from one URL to another URL without impacting the original URL?
It depends what you mean by ‘impacting’. Changing the permalink structure will mean that the URL that a page/post previously was found out will now return a 404 error if a redirect from the old permalink URL to the new one isn’t created.
We also have a guide on changing your permalinks available here: https://yoast.com/help/how-do-i-change-the-permalink-structure/
