Discord.js bot that welcomes new users with a random message. I need help please

client.on('guildMemberAdd', member => {
    const channel = member.guild.channels.cache.find(ch => ch.name === 'welcome');
    if (!channel) return;
        channel.send(`Welcome to the community, ${member}!`);
});

//This works but it only gives out one message... I'd like the ability to have one random message at random to be send to the welcome's channel. I'm very new to creating bots.