I use the following on an ESP32 to retrieve the weather data.
String httpGETRequest(const char* fullURL) {
String payload = "{}";
WiFiClient client;
HTTPClient http;
http.begin(client, fullURL);
int httpResponseCode = http.GET();
if (httpResponseCode == 200) {
payload = http.getString();
} else {
Serial.print("HTTP Response code: ");
Serial.println(httpResponseCode);
}
http.end();
return payload;
}