NodeJS I'm stuck with async

Question

I am new with JavaScript and still have some issues with Promises I guess here is the code doesn't work (actually works in unwanted order):

exports.getSubUsers = (req,res,next)=>{

const subUsers = [];


req.user.subUsers.forEach(subUser=>{
    User.find({_id:subUser._id}).then(user=>{
        subUsers.push(user[0]);
    });
});

console.log(subUsers);
  
}

console.log(subUsers) turns [ ] , What I want is , adding users inside that array