Check out example codes for "html make range bar show value". It will help you in understanding the concepts better.
Code Example 1
function updateTextInput(val) {
document.getElementById('textInput').value=val;
}
Code Example 2
<input type="range" name="rangeInput" min="0" max="100" onchange="updateTextInput(this.value);">
<input type="text" id="textInput" value="">
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