JSFiddle - React, Tailwind, and code Playground

JavaScript

var array =[23,345,6,765,54423,45654,7657,43,43,5,765,3456,768,897,545,645,87,4556,432,543,534];
var chunkEachBy = [3,2,1,5,6,4];

for(var i =0, l = chunkEachBy.length; i < l; i++)
{
     array.splice(i, 0, array.splice(i, chunkEachBy[i]));   
}

console.log(array);