Hello Thomas L'Hotellier
Thank you for reaching out to the Microsoft Q&A platform.
First, it's important to note that, for your virtual machines to have internet access, you need to have a virtual switch configured in Hyper-V Manager that is connected to a physical network adapter on your host machine.
Hyper-V has three types of virtual switches -- external, internal, and private. Create an external switch to share your host computer's network with the virtual machines running on it.
As per the documentation provided below, I am assuming you may have created a virtual switch called "LabServicesSwitch" in Hyper-V Manager. Is that correct? If not, please follow https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/quick-start/connect-to-network. This exercise walks through creating an external virtual switch. Once completed, your Hyper-V host will have a virtual switch that can connect virtual machines to the internet through your host computer's network connection. https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/user-guide/setup-nat-network
https://learn.microsoft.com/en-us/azure/lab-services/concept-nested-virtualization-template-vm
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