I briefly understand the use of call in js, which is used to change the direction of this. For example:

var fn1=function(){
    console.log(1);
}
var fn2=function(){
    console.log(2);
}
fn1.call(fn2);

fn2thisfn1,1.
elementsNodeList
var elements=document.querySelectorAll("div");
Array.prototype.forEach.call(elements,(element)=>{
     console.log(element)
});

callforEachcallback
callBackcallcall