JSFiddle - React, Tailwind, and code Playground

HTML

<input type="button" id="button" value="ボタン">
<p id="display"></p>

JavaScript

let display = document.getElementById("display");
let i = 1;

function countup() {
  display.textContent = i;
  i++;
  setTimeout(countup, 1000);
}

button.addEventListener("click", () => {
  countup();
});