how to update two data in two different tables ?

Explain what are you trying to do, clearly please. Because it doesn't make sense to me.

public function becomeDJ()
{
    // Here you find a channel whose primary key value is 'id'.  That's weird.
    $channel = App\Channel::find('id');

    $channel->user_id = Auth::user()->id;
    $channel->save();

    // Here you find an user whose primary key value is 'type_id'. Also weird.
    $user = App\User::find('type_id');
    $user->type_id = '2';
    $user->save();

    // Here you are returning a view. It would make more sense to redirect to the edit route. Or redirect back to wherever the user making the request came from.
    return view('dashboard.editChannel');
}

@ftrillo can you tell me what I can do?

this is what I am trying to do

if the user clicks on the "take channel" button,

<a href="/become-dj/{{ $channel->id }}/process" class="btn-flat"><i class="material-icons">flag</i></a>

I want to update the type_id in the users table from "3" to "2", which means the user has changed to a dj,

$user = App\User::find('type_id'); //trying to retrieve the id from the user who clicked the button
$user->type_id = '2'; //change the id from "3" to "2", which means the user has changed to a dj
$user->save(); //and save it to the database

and also fill user_id in the channel table with the id of the user who clicked the button

$channel = App\Channel::find(id);  //trying to retrieve the id from the channel selected by the user

$channel->user_id = Auth::user()->id; //updating the user_id on the channel table with the id of the user who clicked on the button
$channel->save(); //and save it to the database

I see

$user = Auth::user(); // This will get you the user that is currently logged in
$user->type_id = '2';
$user->save();

$channel = Channel::find($id); // $id is the id of the channel. It probably comes from the request
$channel->user_id = $user->id;
$channel->save();

That should work. If you want an user other than the authenticated one, you can just user find(), like I did with the channel.

Also, you probably want to save both models inside a transaction, so that if something goes wrong between the two queries, you don't get corrupted data.

That would look like this:

$user = Auth::user();
$user->type_id = '2';

$channel = Channel::find($id);
$channel->user_id = $user->id;

DB::transaction(function() use  ($user, $channel) {
    $user->save();
    $channel->save();
});

I hope this cleared things up a bit for you.

@ftrillo this works like a charm, thanks a lot for helping me

@wardaddy I'm glad it worked. Don't forget to mark this as solved.