Register/login flow with passport in REST API

Hello, I make @vue/cli/axios 4.0.5 app with data reading from Laravel 6 Backend REST API with passport auth driver. I want to clarify register/login flow, as except this I will need also to use passport client toaken for oauth2 connection.

When in register method I create new user, like :

            DB::beginTransaction();

            $requestData= $request->all();
            $newUser = new User();
            $newUser->name= $requestData['name'];
            $newUser->password= Hash::make($requestData['password']);
            $newUser->status= 'A';
            $newUser->email= $requestData['email'];
            $newUser->save();

Have I also to create oauth_clients row with user_id created at rows above? like:

const data = {
    name: 'Client Name',
    ‘user_id’ : $newUser.id, // CONNECT USER USER CREATED ABOVE
    redirect: 'http://example.com/callback'
};

axios.post('/oauth/clients', data)
    .then(response => {
        console.log(response.data);
    })
    .catch (response => {
        // List errors on response...
    });

As I do not create new client in command line

For login I have to use this docs https://laravel.com/docs/6.x/passport#requesting-password-grant-tokens :

Requesting Tokens
Once you have created a password grant client, you may request an access token by issuing a POST request to the /oauth/token route with the user's email address and password. Remember, this route is already registered by the Passport::routes method so there is no need to define it manually. If the request is successful, you will receive an access_token and refresh_token in the JSON response from the server:

$http = new GuzzleHttp\Client;

$response = $http->post('http://your-app.com/oauth/token', [
    'form_params' => [
        'grant_type' => 'password',
        'client_id' => 'client-id',
        'client_secret' => 'client-secret',
        'username' => '[email protected]',
        'password' => 'my-password',
        'scope' => '',
    ],
]);

return json_decode((string) $response->getBody(), true);

That is clear with username and password parameters, but what are client_id, client_secret parameters? have I before running

$response = $http->post('http://your-app.com/oauth/token'

to get oauth_clients(I need to create model for this table ) rows by user_id ?

"laravel/framework": "^6.2",
"laravel/passport": "^8.1",

Thanks!