JSFiddle - React, Tailwind, and code Playground

HTML

<span id="tot1"></span>, <span id="tot2"> und </span> und <span id="tot3"></span>

JavaScript

students = new Array("Paul", "Jan", "Fabian D.", "Fabian K.", "Lennard", 					"Robin", "Angelique", "Joyce", "Sarah", "Ajlin",
"Enes", "Leon", "Boran", "Joshua")    


var arr = []
while(arr.length < 3){
  var randomnumber=Math.ceil(Math.random()*students.length-1)
  var found=false;
  for(var i=0;i<arr.length;i++){
    if(arr[i]==randomnumber){found=true;break}
  }
  if(!found)arr[arr.length]=randomnumber;
}
console.log(arr.valueOf());

tot1 = students[arr[0]];

tot2 = students[arr[1]];

tot3 = students[arr[2]];

document.getElementById('tot1').innerHTML = tot1;
document.getElementById('tot2').innerHTML = tot2;
document.getElementById('tot3').innerHTML = tot3;