Custom chaining in codeigniter4 model

Hi everyone, like suggested in title i would like to do somethings like this:

PHP Code:

$UserModel->Where('age','18')->WithCompanyInfo()->findAll(); 


so, in my UserModel i must create this method WithCompanyInfo that refer to another table / model CompanyModel with external key "user_id".

PHP Code:

  public function WithCompanyInfo ()
  {
    //somehow tell ci4 to make a join and retrieve companymodel info
    return $this;
  } 


How can be done that?
thanks

UPDATE

I've found how to manage that.