How to check if a user is already created, if not, create, else show an error message that a user is created Laravel

I have a registration form in my front page and the goal is to check if a user is already created, if a user already exists, show an error message that a user is already created with given values.

My RegisterController create method now looks like this:

public function create(Request $request) {

    $create = User::create([
        'email' => $request['email'],
        'paypal_email' => $request['paypal_email'],
        'password' => Hash::make($request['password']),
    ]);

    if($create){
        Company::create(['user_id' => $create->id]);
        return redirect('/dashboard');
    }
}

How to check if a user is already created and if yes, show an error message?

via Chebli Mohamed