Configure properties in pnp

Below is the example how can we change the baseurl or other properties in pnp and connect to specific web using pnp in spfx

private pnpSPConfiguration():void

{

let headerOption:any=["Accept","application/json;odata=verbose"];

pnp.sp.configure(headerOption,this.context.pageContext.web.absoluteUrl+"/demo")

.web.lists.get().then(function(response)

{

console.log(response);

});

}