<button class="btn">Click me!!!</button>
body {
    background: #222;
    height: 100vh;
    display: grid;
    place-items: center
}
.btn {
    border: none;
    background: #c7f453;
    padding: .5rem .75rem;
    font-size: 1.25rem;
    border-radius: 5px;
}
const btn = document.querySelector('.btn');

btn.addEventListener('click', function() {
   if(this.innerHTML === 'Click me!!!') {
        this.innerHTML = "Uh yeaaah";
    } else {
        this.innerHTML = 'Click me!!!';
    }
    
})

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