Follow these steps to create the User Subscription Batch Service on the Azure portal.
Sign into Azure portal.
In the dashboard, press "+" and the search for "more services". Then select Subscriptions, as shown below.
In the Subscription blade, choose your subscription type and click Access control (IAM). Then, press Add.
In the "Add Permissions" blade, select the Contributor role, search for the Batch API, and press "Save" to save the permission.
Follow these steps to create a key vault for your Batch Services
In User Subscription mode, an Azure key vault is required which belongs to the same resource group where the Batch account is to be created. Also, we are going to create the Batch Services with User Subscription.
Click New >> Compute and select Batch Service.
In the "New Batch Creation" blade, choose the descriptions as in the image below. For creating the storage account I have chosen the exsisting account, however, if you don't have one then choose the "Create New" option to create a new storage account. Then, choose POOL ALLOCATION to the User Subscription.
For creating the new key vault, choose "Create a new vault" then give the desired description for your vault, and choose "Create" to create the Key Vault.
For keyvault, it shows the newly created key vault. Next, we choose to pin our Batch Service into the dashboard and click "Create" to create the account.
After deployment, we are able to see our Batch Service with User Subscription in detail.
Summary
I hope you understood how to create Batch Service with User Subscription on the Azure portal.