How to setup vyos with pbr and wan loading blance on single vyos router

Hi Teams,
As the picture shown:

I want to setup vyos :

  1. 2 WAN loading balance: I want to setup vyos which will have 4 wan interfaces. line1 and line2 need setup as wan loading balance mode as LB1 . line3 and line4 are working in wan loading balance mode as LB2.
  2. PBR: I also want to setup LB1 and LB2 with policy base routing.

Does anyone know how to setup the configuration like this?

In which step did you stop?
Wan loadbalancing described in our documentation