client.guilds.cache.get(/*server ID*/)
.channels.cache.get(/*channel ID*/)
.send("Hello!")
//Discord.js v13
client.channels.cache.get(channelID).send({ content: "Mesage goes here" })
client.channels.cache.get("<channel>").send("<message>");
message.guild.channels.cache.get(/* channel ID */).send("welcome in this channel!")
client.channels.cache.get("channel ID").send("hello world");
client.guilds.cache.get("<id>").send("<msg>"); // used for specific channel
const channel = client.channels.cache.get('Channel Id');
channel.send({ content: 'This is a message' });