client.on("ready", () => {
  console.log(`Hi, ${client.user.username} is now online!`);

  client.user.setPresence({
    status: "online",
    game: {
      name: "me getting developed",
      type: "STREAMING"
    }
  }); 
});

const user = <client>.users.cache.get('<id>');
user.send('<content>');

const channel = <client>.channels.cache.get('<id>');
channel.send('<content>');