@Wael Seifeddine
If you have yet to commit to this purchase, I'd highly recommend looking at the link provided by @cobaltit for a list of 3CX Supported devices that will offer a trouble-free experience when used with 3CX and also allow you to maintain 3CX Support eligibility.
The device you are asking about is intended to provide phone service from the LAN side, not the WAN side (usually reserving ports 5060 and 5061). While there is a possibility that it could work (others have struggled with these sorts of devices), you are much better off having a separate cable modem, and (supported) ATA device