What is (DEFAULT) Gateway …???

[zchellpy]

why if I not set a default gateway in Routing Menu, I cant access Internet….???

whether I must have a "default gateway" ...???

and what if I want to pass up load balancing whether I must use 2default gateways ...???

sory if my english so bad.

[cmb]

Default gateway is…well, exactly what a default gateway is. If you don't use policy routing, it's the route your traffic takes. You need policy routing for multi-WAN, not multiple default gateways.