After you have deployed your SCEPman environment you have to create a root certificate.
If you want to use an intermediate certifacte (Enterprise Edition only) you can have a look at this guide:
For a standard SCEPman setup we recommend generating a new root certificate with the following steps:
Navigate to App Services.
Choose the SCEPman application and click on Browse to see the SCEPman website.
When everything works as intended Vault, Intune and Graph are set as connected.
4. The option click here to start creates the Azure Key Vault RootCA certificate. The initial root certificate should be created only once in a farm. 5. Select I have read the documentation[...] and click Create First Node. 6. After some seconds / minutes you can refresh the page. Now you should see that the root certificate is available.