Hey there, devops ct4
The error you have seen in the message 'AADSTS16000' means you are signing into the portal with an account that is not registered to a tenant, nor has a subscription (because there is no tenant that has been created).
Please can you try opening an InPrivate browsing window and try signing into the portal using this link: https://portal.azure.com
Please sign into the correct account that has been used to sign up for a subscription. If you haven't subscribed to a subscription yet, please sign up using this link: https://azure.microsoft.com/en-us/pricing/purchase-options/azure-account
Hope this information helps,
Nathan