Drupal 8.x

Since admin_toolbar 8.x-2.* not any longer supported, I have to update to 3.*
Website runs on Ubuntu 20 Server, PHP 7.4
Drupal Version 8.9.18
Profile Commerce Base (commerce_base-)

$ composer require 'drupal/admin_toolbar:^3.0'
./composer.json has been updated
Running composer update drupal/admin_toolbar
> DrupalProject\composer\ScriptHandler::checkComposerVersion
Loading composer repositories with package information
Updating dependencies
Your requirements could not be resolved to an installable set of packages.

Hello everybody,

I have been developing Drupal sites since 2010 and today I admit that I no longer understand anything about the Drupal philosophy ...

My own site is developed in Drupal 7, it uses Drupal Commerce and many modules that have sometimes taken years to achieve a stable version.

Today, I have to develop a commercial site and I have many questions. Indeed when I go to: https://www.drupal.org/project/drupal

I read :

I'm currently building Drupal inside a container, enabling the modules(using drush) and running testcases for the modules. I have ran the testcases for module facets using the vendor/phpunit cli command but its taking more than 30 hours for me. The amount of time is relative to other modules like captcha as well. Any idea why its taking so much time?

On one of my projects (Advanced Help), all the project's permissions come with the following warning:

Warning: Give to trusted roles only; this permission has security implications.

I see there is help module to offer help about a module to the admin.

I want to know if there is any module by which I can offer help to guests or all authenticated users (not just admin).

My idea/use case is like a visitor or authenticated user has come to the site and wants to know what a button is about or what a link is about .... I want to offer a  "what is this" type of icons (at various places on the screen),  clicking on which I can offer "context sensitive help" to the visitor or the user.

Please let me know how to proceed on this.

Thanks