Question about submission form to database

I would recommend you going through the html form at first.

Like,

View : 

PHP Code:

<form action="POST" method="<?php echo base_url('/your_controller/lets_post_it');?>">
   <input type="text" name="member_name" class="blabla" placeholder="Please Insert Your Name"/>
   <input type="text" name="member_username" class="blabla" placeholder="Please Insert Your Username"/>

<button> Send it </button>

</form> 


Controller 

PHP Code:

public function lets_post_it() {

  $name = $this->input->post('member_name);  //first retrieve from inputs
  $username = $this->input->post('member_username');

  $data = array(
     'member_name'=> $name,  // then match with your database
     'member_username' => $username
);

   $this->load->model('My_Model');
  $result = $this->My_Model->upload_it($data);  // and send it to model

  if($result){
      $this->session->set_flashdata('success', 'Data has been inserted successfully');
      redirect($SERVER['HTTP_REFERER']);
}
} 


MODEL

PHP Code:

public function upload_it($data){
  
   $query = $this->db->insert('table_name', $data);

   return $query;
}