how to make a ping in discord.js

// If the command sent in the chat is "ping"
if(cmd === `${prefix}ping `) {
  
  // It sends the user "Pinging"
        message.channel.send("Pinging...").then(m =>{
          // The math thingy to calculate the user's ping
            var ping = m.createdTimestamp - message.createdTimestamp;

          // Basic embed
            var embed = new Discord.MessageEmbed()
            .setAuthor(`Your ping is ${ping}`)
            .setColor("Your Color")
            
            // Then It Edits the message with the ping variable embed that you created
            m.edit(embed)
        });
    }if(cmd === `${prefix}ping`) {
        message.channel.send("Pinging...").then(m =>{
            var ping = m.createdTimestamp - message.createdTimestamp;
            var botPing = Math.round(bot.pi);

            m.edit(`**:ping_pong: Pong! Your Ping Is:-**\n  ${ping}ms`);
        });
    }  if(!message.content.startsWith(prefix) || message.author.bot) return;

     const args = message.content.slice(prefix.length).split(/+/);
     const command = args.shift().toLowerCase();

     if(command === 'ping'){
         message.channel.send('pong');
     }