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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