JSFiddle - React, Tailwind, and code Playground

HTML

<form id="leFormulaire" action="/echo/html/" method="post">
  <button type="submit" id="leBoutton">
    Cliquez pour envoyer le formulaire
  </button>
</form>

CSS

html,
body {
  height: 100%;
  margin: 0;
  display: flex;
  justify-content: center;
  align-items: center;
}


button {
  border: 0.25em;
  padding: 1em;
  font-size: 1.2em;
  cursor: pointer;
}

button.confirm {
  background: green;
  color: white;
}

JavaScript

const form = document.getElementById("leFormulaire")

const onSubmitEvent = (event) => {
  event.preventDefault()

  const button = document.getElementById("leBoutton")
  button.classList.add("confirm")
  button.textContent = "Cliquez une seconde fois pour valider"

  form.removeEventListener("submit", onSubmitEvent)
}

form.addEventListener("submit", onSubmitEvent)