Answers for "how to check if you can dm a member on discord js"

see if discord message is in dm discord.js

if(message.channel.type === 'dm'){
	message.channel.send("Pog");
}

discord.js check if member is in server

// guild = server
let guild = client.guilds.get('guild ID here'),
  USER_ID = '123123123';

if (guild.member(USER_ID)) {
  // there is a member in this guild with that ID
}