I created a Partner Account from my Shopify Account and a Development in, but now I can't delete said store. I tried following the steps in https://community.shopify.com/c/Shopify-APIs-SDKs/How-to-delete-Dev-shops/td-p/134832 but when I go to "Plan and permissions" I don't see any "Close store" button, even though I'm the store owner.
You can archive the store by clicking into it and selecting archive. This won't remove it from the list, but you will see the store greyed out. The linked forum post was from 2014 and our UI has been updated.
You have an option to move the store to another email. Go to your account page https://accounts.shopify.com/accounts/... . There you can see the list with all your stores. Tap Exclude from Shopify ID
here is the option to archive it