Shopping for laptops - customization??

Just a general note on shopping for laptops on Dell website.

The so called "customization" offered seems to only be the offers of additional accessories or service agreements.

Real customization would include, for example, the ability to increase RAM from 8gb to 16 gb or from a 250gb SSD to 500gb SSD on a particular system. After spending some hours shopping for the exact configuration in a laptop that i want on the website there appear to be no options like this.

Also i wish Dell would be a bit clearer about the tech behind their display panels eg VN TN or IPS instead of using general terms like Wide Viewing Angle. Unless specified i assume they are TN type panels?