Hi there @Welly!
Don here from Shopify.
If you're looking for a way to feed your Shopify products to your Pinterest account, you can check out some of the Pinterest apps available in our store.
It looks like GMCFeed specifies that it can feed products to Pinterest, so it might be a good one to check out first.
As with all third-party apps in our store, you can reach out to the developers directly with any support queries you have by using the contact details listed there on the app store page.
All the best!