Hi @Mitchell Darry,
Thanks for contacting Microsoft Q&A platform.
A user will need "VM Contributor role" or a custom role with privileges to power off\on, if they need to shutdown a VM via a portal or powershell or azure command line.
It is also possible to schedule a shutdown through "auto shutdown" feature, available in the left menu for vm under "Operations" > "Auto shutdown".
Connect-AzAccount #Authenticate to Azure
Set-AzContext -Subscription <subscription name> # set the correct subscription
Stop-AzVM -ResourceGroupName <Resource group> -Name <Virtual machnie name>
Read more about build in VM roles: https://learn.microsoft.com/en-us/azure/role-based-access-control/built-in-roles
Read about setting custom roles: https://learn.microsoft.com/en-us/azure/role-based-access-control/custom-roles
Read about assigning roles to an account: https://learn.microsoft.com/en-us/azure/role-based-access-control/role-assignments-portal
Read about auto shutdown: https://learn.microsoft.com/en-us/azure/automation/automation-solution-vm-management
Hope this helps you.