custom role creation a plugin

thanks for your answer.

I will write the actions i have allready done about that task and the thoughts i am having about its completion

I have created a custom role. I used MEMBERS plugin. I named the role manager and i gave him the capability to create users and to edit users.

I remind you that i want him to be able to create a SPECIFIC number of a SPECIFIC role.

I have a thought and i want some advice here. I should mention that i can code but i am new in WP. That is a solution a would probably follow if i had chosen to built this custom and not through WP

I am thinking to first go to database and add the field MANAGERID to users table
Then i am considering of building a form. I mean Pages –> New –> html tab –> and build a page with a form.

In this new page i will restrict the access only to members with the role of manager. (i have already tried that succesfully using a memberhip plugin)

This form should contain the necceserry fields of a new user. Submiting the form the data goes to table alongdide with the managerid of the manager.

In that way i can count the users each manager created and i can both
-manage the edit to the right users and
-manage to limit the number of users created.

I do not have a clue how to set the roles for the created users

Is that a valid doable solution?
I am really open to any other suggestions, tips or anything relevant

Thanks for the answer.
I surely do not have a plugin like this. I just mentioned my thoughs about dealing with the issue I descriped in my previous post.

I understand your feedpack about changing the datadase. I will try to think of another solution.
If you have an algorithm about solving that please share

Ok.
I have implemented the task. I am writing the solution i came up for two reasons
-i reaaly need some feedback about the solution ( i am new in WP and i do not want to find any suprises i didn’t see when the system is up and running)
-To share with other members that perhaps are looking for something like this

Steps

• i installed MEMBERS plugin. I created two custom roles with names coyotemanager and coyotestudent. I gave to the coyotemanger the capability to create and edit users.
• I installed the plugin MEMBERSHIP 2. i created 2 memberships. Manager and student. I connected those memberships with the same roles using this code (put in functions.php of your theme)

  add_action( 'ms_model_relationship_create_ms_relationship_before', 'ms_controller_member_assign_memberships_done_cb', 99, 4 );
  function ms_controller_member_assign_memberships_done_cb( $membership_id, $user_id, $gateway_id, $move_from_id ) {
  	$user = new WP_User( $user_id );
  	switch( $membership_id ){
  		case 5814: //found it in MEMBERSHIP 2
  			$user->set_role( 'coyotemanager' );
  			break;
  
  		case 5844:
  			$user->set_role( 'coyotestudent' );
  			break;
  	}
  }

• I created a WP page. I gave access to this page only to coyotemanager.
• I wrote a php snippeset. the current user (coyotemanger only) can create a specific amount (you specify it into the code) of students.

  <?php
  $servername = "localhost";
  $username = "root";
  $password = "";
  $dbname = "ld";
  
  $conn = new mysqli($servername, $username, $password, $dbname);
  // Check connection
  if ($conn->connect_error) {
      die("Connection failed: " . $conn->connect_error);
  }
  
  //get the number of students//////////////////////////////////////////////
  $sql="SELECT * FROM wp_usermeta
  WHERE meta_key ='description' and meta_value='".get_current_user_id()."'";
  $result = $conn->query($sql);
  	$num_students = mysqli_num_rows($result);
  	echo "Σύνολο μαθητών σου:".$num_students."";
  ///////////////////////////////////////////////////////////////////////////
  
  //create sql to get the name and lastname od teacher's student////////////////////
  $i=1;
      while($row = $result->fetch_assoc()) {
  	   $query[$i] = "SELECT * FROM wp_usermeta WHERE user_id ='".$row["user_id"]."'";
  		//echo  "query=".$query[$i];
  		$i++;
  
  	}
  ///////////////////////////////////////////////////////////////////////////////////
  
  //run the queries get name and last name and print///////////////////////////////////////
  $j=1;
      while ($j !== $num_students+1)
  	{
      $result1 = $conn->query($query[$j]);
  		while($row = $result1->fetch_assoc()) {
  
  		    if ($row["meta_key"] === "first_name"){
  		      $userdataname= $row["meta_value"];
  		     }
  
  		    if ($row["meta_key"] === "last_name"){
  		     $userdatalname = $row["meta_value"];
  		     }
  
          }
  		 echo "id: " . $row["user_id"]. " - Name: " . $userdataname. " " . $userdatalname. "";
  		$j++;
  	}		
  
  	if ($num_students <3)// 3 users
  	{
  	echo "may add still ". 3-$num_students."μαθητές
  
  ";	
  
  	echo'	<form name="usercreation" method="POST" onsubmit="return form_validation()" action="../usercreation.php">
          Name: <input type="text" id="student_name" name="student_name" />
          Last Name: <input type="text" id="student_lname" name="student_lname" />
          Email: <input type="text" id="student_email" name="student_email" />
          username: <input type="text" id="username" name="username" />
  
          <input type="submit" value="Submit"/>
       </form>';
  
  } else {
      echo "No more users";
  }
  $conn->close();
  
  ?>

  The php file usercreation.php (form action)

  <?php
  // Get data
  require_once('wp-load.php');
  
  $student_name = $_POST["student_name"];
  $student_lname = $_POST["student_lname"];
  $student_email = $_POST["student_email"];
  $username = $_POST["username"];
  
  if( null == username_exists( $username ) ) {
  
    // Generate the password and create the user
    $password = wp_generate_password( 12, false );
    $managerid= get_current_user_id();
    $userdata = array(
      'user_login'  => $username,
  	'description'  => $managerid, //store the manager's id into students data
      'first_name'  => $student_name,
  	'last_name'   => $student_lname,
      'user_pass'   => $password,
  	'user_email'  => $student_email,
  	'role'   => "coyotestudent"
  );
  
  $user_id = wp_insert_user( $userdata ) ;
  
  //On success
  if ( ! is_wp_error( $user_id ) ) {
      echo "User created : ". $user_id;
  }
  else{
  	 $error_string = $user_id->get_error_message();
     echo '<div id="message" class="error"><p>' . $error_string . '</p></div>';
  
  }
  
     // Email the user
   wp_mail( $email_address, 'Welcome!', 'Your Password: ' . $password ); 
  
  } // end if
  
  ?>

  Still needs form validation and css