Simple get with fetch API

index.html

<button type="button" id="btn">Show my IP</button>  
<div id="ipContainer"></div>
<script>
const btn = document.getElementById('btn')
const ipContainer = document.getElementById('ipContainer')

const fetchJSON = async (req) => {
  const request = await fetch(req)	
  return request.json();
}

btn.addEventListener('click', async () => {
  ipContainer.innerHTML = "searching..."
  const data = await fetchJSON('http://httpbin.org/ip')
  ipContainer.innerHTML = `<h1>${data.origin}</h1>`
})
</script>