Telegram: Control ESP32/ESP8266 Outputs

Yes.
You can add more user IDs to your code. For example:

#define CHAT_ID_1 "XXXXXXXXXX"
#define CHAT_ID_2 "XXXXXXXXXX"

Then, in this line of code you must check all the valid IDs:

if (chat_id != CHAT_ID_1 || chat_id!=CHATID_2) {
  bot.sendMessage(chat_id, "Unauthorized user", "");
  continue;
}

I hope this answers your question.
Regards,
Sara

Thanks Sara.