I want to submit multiple users if checkbox is checked

The following code is getting all terms and see if any one of them is checked or not. If any term is checked a form should show under the selected checkbox with email, the username(auto-generated) and password(auto-generated), and admin should be available to submit each form which will create a user for a specific term.

The problem is The form is being submitted to options.php which I have to submit checkboxes in the options table

div class=wrap
            ?php screen_icon(); ?
            h2Subdomain Settings/h2           
            form method=post action=options.php
            ?php
                // This prints out all hidden setting fields
                settings_fields( 'subdomain_option_group' );   
                do_settings_sections( 'subdomain-admin' );
                submit_button(); 
            ?
            /form
        /div

        $selected = $this-options;
        $terms = $GLOBALS['wpdb']-get_results( SELECT * FROM wp_terms, OBJECT );
//      $terms = get_terms();
//      echo plugin_dir_url( __FILE__ ) . 'subdomain-users.php';
        foreach($terms as $term) {
            ?div class=wrap ?php
                ? input id=in-category-?php echo $term-term_id ? type=checkbox name=post_category[] ?php echo in_array($term-term_id, $selected['subdomain_cat']) ? checked : ; ? value=?php echo $term-term_id; ?  
                label for=in-category-?php echo $term-term_id ? ?php echo $term-name; ?/label
                ?php
                if(in_array($term-term_id, $selected['subdomain_cat'])) {
                    ? div style=margin-bottom: 25px; ?php
                        ? form method=post action=?php
                        ? h2?php echo Category : .$term-name.'br/'; ?/h2 ?php
                        ? input type=email placeholder=Enter Your Email: name=email ?php
                        ? input required type=text placeholder=Enter Your Name: value=?php echo $this-generate_user_name($term-name); ? name=name ?php
                        ? input required type=text value=?php echo $this-randomPassword() ? placeholder=Enter Your Password: name=password ?php
                        ? input type=submit name=user_save id=user_save class=button button-primary value=Save User?php
                        ? /form ?php
                    ? /div ?php
                }
            ?/div?php
            
        }

Please let me know how do I submit this form to create user for each term And I want to add a role and permission too which will allow the created user to select only the relevant term(category) for post and he will be author for only that category.

Thanks