Module development and code questions

Hi, I've been working on an offsite payment gateway module. I reached upto the point of redirection, but I cannot receive a proper successful order becoz I hit this error just during the redirection back to site happens. I checked log report, found this:

Path: /checkout/16/payment/return. Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException: in Drupal\Core\Routing\AccessAwareRouter->checkAccess() (line 118 of /...../core/lib/Drupal/Core/Routing/AccessAwareRouter.php).

I have 2 boolean fields in some of my content types and I want to filter content based on the values on these boolean fields. I am editing the built in content view.

For demonstration purposes lets think the fields are `field_boolean_1` and `field_boolean_2`.

I have programmatically added a dropdown like this with hook_form_alter():

Hello community !

I looking for, the good code for intercept and redirect the save button (/user/1/edit) on my api.

i try this :

The question is in the title !
I need session_id in hook_user_login.
I can get user name, user id, but no success for sessionid

 I tried  $session_id = \Drupal::service('session')->getId(); //empty

Thanks in advance for your help 

Edit: If I cannot get the id, how can I get the hash that is stored in base ?.

I'm using the commerce_email module, to send emails to customers upon events fired.

When an order is complete, I do send an email to the customer with info about tracking codes and so o, and want to attach an pdf with further info about tracking, is that possible, and how ?

Thank you in advance.

Building my first Drupal site. Drupal 10.

I have a Content Type called "Kind of Things", say, which has a field "Amount of these kind of Things", say.

I'd like to construct a block which displays a count of nodes in "Kind of Things" and a sum of the integer fields "Amount of these kind of Things".

Something like "There are 56 different kinds of things, a total of 1089 things in all".