How to connect two IPoE lines

[squid-c]

I am trying to use two IPoE lines in one fortigate.

The configuration is as follows.
IPoE①: for Internet
IPoE②: for maintenance such as Windows Update

How should we configure it?
I know how to set up only one line.
Should I use VDOM?

It is version 7.4.3.

Thank you for any answer
Best regards

[AlexC-FTNT]

There is close to no information on IPoE, but as I see, the DHCP is assigning IP addresses based on the Physical info of the devices. So if the user lands on another VLAN, it may get another IP address assignment (from a different DHCP server configured). Is there any limitation on using VLANs for IPoE? I don't imagine how this can be done with only a single connection from PC to the switch/FortiGate