How do I change the enabling policy of k8S custom scheduler

Question

I have a project to enable another scheduler, This requires modifying the enabled policies and weights. After kubernetes 1.19, it can be set by KubeSchedulerConfiguration， although it is still in the beta stage.

My project is kubernetes 1.18, how do I view the default policies and how do I override or modify some policies and weights

I really appreciate any help with this