Hi Sebastian Antunez Noguera,
Thank you for reaching out to us on the Microsoft Q&A forum.
To enable RDP access to your VMs in Windows Admin Center, ensure that Remote Desktop is enabled on each VM by going to System Properties > Remote and selecting "Allow remote connections to this computer." Make sure the inbound rule for Remote Desktop (TCP port 3389) is enabled in Windows Defender Firewall on each VM. Verify that the VMs are on a network that allows RDP traffic and that they are powered on and reachable. Check that your user account has the necessary permissions to access the VMs.
Please find the below document for more information: Enable Remote Desktop on your PC
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