AR750s VLAN100 on the WAN port/ connection

hi there, I would like to check if that is possible to setup (with the normal FW) the internet connection on the WA port with the below settings
Gateway IP: XXX.XXX.XXX.XXX
WAN IP: XXX.XXX.XXX.XXX
Subnet Mask: XXX.XXX.XXX.XXX
Primary DNS Address: XXX.XXX.XXX.XXX
Secondary DNS Address: XXX.XXX.XXX.XXX
VLAN: 100
The normal IP settings are fine, but I don’t fine the Vlan option that could be added to the WAN port. unfortunately, without that, the internet won’t work.

you need to go to Luci under more settings > advanced.
under Network > Switch
add VLAN 100, tagged off off tagged