Check out example codes for "html use js variable as text". It will help you in understanding the concepts better.

Code Example 1

<h1>"My number: " <span id="myText"></span></h1>

<script>

	//You can use an IIFE (Immediately Invoked Function Expression)
	(() => {
  		var number = "123";
		document.getElementById("myText").innerHTML = number;
	})();
</script>

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