To upgrade the free version of YOAST to the premium version, you must follow these steps:
Upload the Yoast SEO Premium plugin, but do not activate it.
Disable the free version of Yoast SEO.
Now, activate Yoast SEO Premium.
All the data from the free version will be automatically used by the premium version.
To enable advanced Features of Yoast Seo Premium, follow the instructions on this article: https://kb.yoast.com/kb/remove-advanced-yoast-seo-settings/