Spreadsheets formula for calculating the tax base in Georgian Lari

Larry.gs

function Larry(date, summ, currency) {
  try {
    var formattedDate = Utilities.formatDate(date, Session.getScriptTimeZone(), "yyyy-MM-dd");
    var apiUrl = "https://nbg.gov.ge/gw/api/ct/monetarypolicy/currencies/en/json/?currencies=" + currency + "&date=" + formattedDate;
    var response = UrlFetchApp.fetch(apiUrl);
    var data = JSON.parse(response.getContentText());
    var rate = data[0].currencies[0].rate;
    var summ = parseFloat(summ.toString().replace(",", "."));
    var result = summ * rate;
    return result;
  } catch (error) {
    return String(error);
  }
}

Paste the code to Extensions > Apps Script
Run it and give permissions to fetch data.

Use as a formula:

=Larry(A2;B2;C2)

Example sheet.