Azure does not support custom DHCP services. You'll have to use the one provided by the platform.
You can deploy an Windows Server Azure VM hosting the DHCP server role, but that's intended for providing IP address leases to your on-premises devices via DHCP relay agent (more at https://learn.microsoft.com/en-us/azure/virtual-network/how-to-dhcp-azure ) - not to Azure VMs.
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hth
Marcin