laravel 7 add relation to user code example

Example 1: laravel where has

use Illuminate\Database\Eloquent\Builder;

// Retrieve posts with at least one comment containing words like foo%...
$posts = App\Post::whereHas('comments', function (Builder $query) {
    $query->where('content', 'like', 'foo%');
})->get();

// Retrieve posts with at least ten comments containing words like foo%...
$posts = App\Post::whereHas('comments', function (Builder $query) {
    $query->where('content', 'like', 'foo%');
}, '>=', 10)->get();

Example 2: how to use where relationship laravel

Event::with(["owner", "participants" => function($q) use($someId){
    $q->where('participants.IdUser', '=', 1);
    //$q->where('some other field', $someId);
}])