feature/improved the getting of rates

src/util/exchangeRate.js

@@ -0,0 +1,18 @@
+const countries = require("./countries.json").countries;
+
+async function getRates(country) {
+    let abbr;
+    countries.forEach(c => {
+        if (c.country === country) {
+            abbr = c.currency_abbreviation;
+        }
+    });
+
+    const res = await fetch(`https://api.frankfurter.dev/v1/latest?base=${abbr}`);
+    const data = await res.json();
+    let rates = data.rates;
+
+    return rates;
+}
+
+module.exports = getRates;