Here is my code so far. How can I achieve what I need to using JavaScript?

var form = document.getElementById('form-body')

var error = []

form.addEventListener('submit', function(e){
    e.preventDefault();

    var name = document.getElementById('name');
    var phone = document.getElementById('phone');
    var email = document.getElementById('email');
    var bday = document.getElementById('bday');

    if (phone.value !== [0]{1}?[9]{1}?[0-9]{9})
        alert('Follow the correct format (09XXXXXXXXX)')    
    
})