Hi @KatherineKnight-8498,
Based on your query, you would like to check how to assign roles for a user in subscription.
You can assign user with roles in subscription using the following document: Assign a user as an administrator of an Azure subscription with conditions.
If you would like to have a customized role, you can follow this document: Understand Azure role definitions. here you can have the role with certain permissions (Actions) so that you can edit the permissions of the role on how much a user can have the access on the subscription.
I hope this information is helpful. Please feel free to reach out if you have any further questions.
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