Can't connect to the IoT platform

What if an embedded device can’t connect to the IoT platform?

which specific embedded device? Your link goes to non-Digi produtcs?
To which specific IoT platform?
Are you talking about Digi Remote Manager (DRM)? : https://remotemanager.digi.com
IoT Device Monitoring - Centralized Remote Device Management Solution - Digi Remote Manager | Digi International

i also dont know how to do it