How to Migrate Data From Craft CMS Commerce Website to Sanity

I need to migrate data from a Craft cms commerce website to sanity which is the best way todo this ?

Hi ! Check out this guide and see if that makes sense to you https://www.sanity.io/guides/guide-importing-data-from-external-sources

I'm copy pasting manually from WordPress. To be fair, i only have about 60 posts 😄

Copying manually is one approach, but this is an e-commerce site with more than 240 product entries and hundreds of product variants which could be a little longwinded , would it be possible to link through GraphQL and transfer data that way ?

AFAIK there no way to import via graphql. Either you need to export your data to ndjson and use the cli to import, or write an import script as described in the guide above.Also see more here:
https://www.sanity.io/docs/importing-data