You can create a virtual machine (VM) in Azure using Azure portal, Azure Powershell.
Using Azure Portal, you can create a new VM by attaching the VHD to the new VM as an OS disk. Create a snapshot and then create a disk from the snapshot. This strategy allows you to keep the original VHD as a fallback. After you have the managed disk VHD that you want to use, you can create the VM in the portal. The steps are described here.
You can also use PowerShell to upload a VHD of a generalized VM to Azure, create an image from the VHD, and create a new VM from that image. You can upload a VHD exported from an on-premises virtualization tool or from another cloud, as described here.