JSFiddle - React, Tailwind, and code Playground

JavaScript

var data = '[{"currency_value":"1.00","currency_code":"47","type":"BUY"},{"currency_value":"1.00","currency_code":"47","type":"SELL"}]'

var data = JSON.parse(data);

var obj = data.filter(function (el) {
    return el.type === 'SELL';
})[0];

console.log(obj);

    function getDataByType(data, type) {
        return data.filter(function (el) {
            return el.type === type;
        });
    }

console.log(getDataByType(data, 'SELL'))