Creating a Random Harry Potter Quote Discord Bot in CPP (DPP)

I just have a general question.

I'm trying to create a discord bot that responds to slash commands and the book title within the Harry Potter series (e.g /Prince of Azkaban) and it will generate a random quote from the book to the channel (it would be nice to have it display a random image from the movie scene it derived the quote from ...but.... that seems too complicated lol).

I've set up the default discord bot that is within the set-up articles (/ping and get ping pong!--------that is embedded down below) but I actually have no idea where to start.

Should I be starting with creating the random generator and then later on finding out how to link it so random quotes can be chosen (i.e a text doc?) or should I figure out where/how I am going to get the book quotes?

Any help is appreciated on how to start!

`

#include "MyBot.h"
#include <dpp/dpp.h>

/* Be sure to place your token in the line below.
 * Follow steps here to get a token:
 * https://dpp.dev/creating-a-bot-application.html
 * When you invite the bot, be sure to invite it with the 
 * scopes 'bot' and 'applications.commands', e.g.
 * https://discord.com/oauth2/authorize?client_id=940762342495518720&scope=bot+applications.commands&permissions=139586816064
 */
const std::string    BOT_TOKEN    = "MY TOKEN";

int main()
{
    /* Create bot cluster */
    dpp::cluster bot(BOT_TOKEN);

    /* Output simple log messages to stdout */
    bot.on_log(dpp::utility::cout_logger());

    /* Handle slash command */
    bot.on_slashcommand([](const dpp::slashcommand_t& event) {
         if (event.command.get_command_name() == "ping") {
            event.reply("Pong!");
        }
    });

    /* Register slash command here in on_ready */
    bot.on_ready([&bot](const dpp::ready_t& event) {
        /* Wrap command registration in run_once to make sure it doesnt run on every full reconnection */
        if (dpp::run_once<struct register_bot_commands>()) {
            bot.global_command_create(dpp::slashcommand("ping", "Ping pong!", bot.me.id));
        }
    });
}

`