How to Perform Advance Format using Maatwebsite Export

I am trying to export my report to excel in my Laravel 5.8 project using Maatwebsites:

In Laravel-5.8, I am trying to export to Excel using Maatwebsite:

<?php

namespace App\Exports;

use App\User;
use Auth;

class StudentExport implements FromCollection, ShouldAutoSize, WithHeadings, WithMappings
{

    private $headings = [
        'Student ID', 
        'Name',
        'Class',
        'Status',
        'Teacher'
    ];

    public function collection()
    {
        $userCompany = Auth::user()->company_id;
        $userEmployee = Auth::user()->employee_id;
        $userId = Auth::user()->id;
        $employeecode = Auth::user()->employee_code;

        $current_terms = DB::table('appraisal_identity')->select('term_name')->where('company_id', $userCompany)->where('is_current', 1)->first()->term_name;
        $identities = DB::table('appraisal_identity')->select('id')->where('company_id', $userCompany)->where('is_current', 1)->pluck('id');
        $publishedgoals = AppraisalGoal::select('employee_code')->where('is_published', 1)->where('appraisal_identity_id', $identities)->where('company_id', $userCompany)->groupBy('employee_code')->get();  


        $published_goals = DB::table('hr_students AS e')
                    ->join('hr_employees AS em','em.id','=','e.teacher_id')
                     ->select(
                        'e.student_id',
                        DB::raw('CONCAT(e.first_name, " ", e.last_name) AS full_name'),
                        'e.student_class,
                        DB::raw('(CASE WHEN e.is_status = 3 THEN "Excellent" WHEN e.is_status = 2 THEN "Good" WHEN e.is_status = 1 THEN "Average" ELSE "Pass" END) AS student_status') 
                        DB::raw('CONCAT(em.first_name, " ", em.last_name) AS teacher_name')
                        
                 )
                    ->whereIn('e.student_id', $publishedgoals)
                ->distinct()
                ->get();

            $published_goals = $published_goals->unique('student_id');
       
           return collect($published_goals);
    } 

public function map($published_goals): array
{
    return [
       $published_goals->student_id,
       $published_goals->full_name,
       $published_goals->student_class,
       $published_goals->student_status,
       $published_goals->teacher_name,
   ];
 }  


public function headings() : array
{

    return $this->headings;
}    

public function registerEvents() : array
{
    return [
        AfterSheet::class    => function(AfterSheet $event) {
            $cellRange = 'A4:E4'; // All headers
            $event->sheet->getDelegate()->getStyle($cellRange)->getFont()->setSize(14);
            $event->sheet->getDelegate()->getStyle($cellRange)->getFont()->getColor()
                   ->setARGB(\PhpOffice\PhpSpreadsheet\Style\Color::COLOR_WHITE);
            $event->sheet->getDelegate()->getStyle($cellRange)->getFill()
                   ->setFillType(\PhpOffice\PhpSpreadsheet\Style\Fill::FILL_SOLID)
                   ->getStartColor()->setARGB('FF17a2b8');
            $event->sheet->setAutoFilter($cellRange);
        },
    ];
  }   

}

I have written the code above to get this resuld:

https://i.stack.imgur.com/IJFTA.png

However I want to:

However I want to:

1. Merge A1:E1 and align center as STUDENT TERMINATION REPORT

2. I want to make D2 to have the output of these variables together: $current_terms - $identities (For example, if $current_terms = 1st Term and $identities = 20. Then It will be 1st Term - 20 )

3. I want to display the current date and time as A2:B2 (Report Date & Time: 20 July 2020 10:00 p.m.)

4. A4:E4 as the Heading (A4->Student ID, B4->Name, C4->Class, D4->Status, E4->Teacher

The result should be as shown below:

https://i.stack.imgur.com/bnxHO.png

How do I modify the code and formatting to achieve this?

Thank you