To start a Hyper-V virtual machine from the command line, you can use the following methods:

Start-VM cmdlet: This method requires PowerShell. Run the following command:
Start-VM -Name <VMName>

Replace with the actual name of the virtual machine you want to start.

Hyper-VUtils.exe: This method requires the Hyper-VUtils.exe tool, which is included with Hyper-V. Run the following command:
HyperVUtils.exe startvm <VMName>

Replace with the actual name of the virtual machine you want to start.

Resumevm option: If the virtual machine is paused, you can use the resumevm option to resume it. Run the following command:
resumevm <VMName>

Replace with the actual name of the virtual machine you want to resume.