can someone help me how to make my main.js file read another .js file only with one command?

Here is that command:

client.on('voiceStateUpdate', (prevMember, newMember) => {
    
    console.log('old: ', prevMember)
    console.log('new: ', newMember)
    //let channel = newMember.channel
    let channel = "800656175297200149"

    const generalChannel = client.channels.cache.get(channel)
    
    // if it's the first person joining voice, notify everyone
    if (!prevMember.channelID) {
        generalChannel.send(`@everyone ${newMember} just hopped on voice. WARWEEK Tribe go see what's up!`)
    }