I have not touched js in years, hense I'm quite rusty in terms of coding in javascript. If you have answers, feel free to tell me and critizise! Inside ping.js

const { SlashCommandBuilder } = require('@discordjs/builders');

module.exports = {
    data: new SlashCommandBuilder()
        .setName('ping')
        .setDescription('Replies with Pong!'),
    async execute(interaction) {
        return interaction.reply('Pong!');
    },
};

in my bot.js file

client.commands = new Collection();
const commandFiles = fs.readdirSync('./src/commands').filter(file => file.endsWith('.js'));

for (const file of commandFiles) {
    const command = require(`./src/commands/${file}`);
    client.commands.set(command.data.name, command);
}

client.on('interactionCreate', async interaction => {
    if (!interaction.isCommand()) return;

    const command = client.commands.get(interaction.commandName);

    if (!command) return;

    try {
        await command.execute(interaction);
    } catch (error) {
        console.error(error);
        await interaction.reply({ content: 'There was an error while executing this command!', ephemeral: true });
    }
});