Module development and code questions

From the configuration form that is loaded when a new block is being placed, or existing block configuration is being edited, how can one determine, programmatically, if the active form is for a new block or configuring an existing block?

This appears to be possible as the form itself changes the access to the machine name property between a new block and existing block, but I haven't been able to figure out what property it is looking at or where this part of the form is being built from.

When I find a function in the Drupal API, how do I work out how to actually use it?

This may not be the right function for doing this, but for example, I want to get a list of all the libraries that have been loaded to a page and looking through the API documentation, I found public function AttachedAssets::getAlreadyLoadedLibraries, how would I work out how to actually call this function in my code? 

Hi 

I have select box with allowed values and it has related many related existing content. I tried function hook_post_update_ function. 

Unable to upload/Delete an image in all content type in Drupal 9 website.

receiving an ajax error in console

So, before accessing the real API endpoint, I've set a policy in Azure API Management that will cache tokens and self-authenticate. If there is a method to save these policies in a source control system, such as Azure DevOps or Github, and fetch them from there, or if the Azure site can handle source control, that would be great. Any suggestions or ideas would be greatly valued.

I'm using drupal 7.55. I've added a webform on several pages using an entity reference of a webform. However, i'm not able to view it as an unauthenticated user but i can view it as authenticated user. 
I've carefully checked roles and permissions several times for this entity reference and it is set to admin role as well as anonymous users.
What else can i do regarding this ? Please help thanks.