Hi ,
Thanks for reaching out to Microsoft Q&A.
(1) I hope to delete the Fabric-account (there is almost no information in it and certainly no important information);
this would be the best option, if you don't have any data you can go ahead and delete. Remember, azure subscription/account has nothing to do with Microsoft fabric account. Fabric is completely isolated and individual ecosystem. In fact you can utilize the ADF, Synapse or PBI from within the fabric workspace and no need to create them separately with azure subs.
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