I'm new to a Contao project, and the only dev at the project....

A custom module is created. For this custom module there is a data entry form (defined in a php file in the `dca` folder), in which a user can enter all the data which is then stored in a custom table.
The code for the module follows the layout stated in the blogpost 'Create a custom module - the basics' (<http://blog.qzminski.com/article/create-a-custom-module-the-basics.html>).

I've seen a PHP page (in the `templates` folder) which gets all the data from the custom database table (gets autoinjected via a variable?) and formats that in a html table.

That is what is built so far.

Now what I want to do is to create a display page for an individual item. Normally that will be: 

* create a link in the existing html table (with the id of the record)
which links to a new page (so for instance
`pagenamewhichidonotknow?id=34`)
* and on that page, receive the id which is sent by the link (get it from the `querystring`?),
* get the data from the custom databasetable (don't know how)
* and then create a nice page (do know how to do this ;-))

I realize this is a large question, but I really don't know where to start. 
Googling shows me a lot of pages with this warning "This guite was written for Contao 2.x and a lot of it's information is outdated! Read with care and only use as a general-purpose guide." and other pages are in German, which is, despite having learned it for 3 years in highschool, not my usp.

Any help is appreciated.