Scopes
A key carries only the permissions you tick.
What each one allows
Send your shop's data (ingest:write) is only for a shop whose products, stock and sales come in through the API.
Read your catalogue and orders, read your reports, read proposed orders, send orders, receive deliveries, stop reordering, and receive webhooks are available to every shop, including one on Shopify.
A demo shop uses a test key only.