JSFiddle - React, Tailwind, and code Playground

HTML

<div>
<p id="myPara">
$200 some $100 content goes $300 here
</p> 
    <p id="convertedPara"></p>
    </div>

JavaScript

function convert() {
         var replacedText = document.getElementById('myPara').innerText;
         var newCurrencySymbol = 'EUR';
         var currencyConversionFactor = 1/1.2567;
         var numberPattern = /\$\d+/g;
         var numbers = replacedText.match(numberPattern);
         for (var i = 0; i < numbers.length; i++) {
             // extract numerical value
             var num = numbers[i].match(/\d+/);
             // your currency conversion here
             var crude = num * currencyConversionFactor;
             var rounded = Math.round(crude * 100) / 100;
             var newNum = rounded + " " + newCurrencySymbol;
             replacedText = replacedText.replace(numbers[i], newNum);
         }
         document.getElementById('convertedPara').innerText = replacedText;
     }

convert();