Replace memory in HP Envy ALL-IN-ONE 27-B245SE

HP has a Video on doing  it: https://www.youtube.com/watch?v=hZXA9coMxCc 
The Service manual is here: https://www.manualslib.com/manual/1113095/Hp-Envy-Pro.html?page=18#manual 

Wesley... that video shows you how to literally remove the memory sticks only... not how to get to them... the manual is for the wrong model.

You indicated you had an HP Envy, per HP: Support document provides specifications and component images that reflect the original design intention for all PCs of this model.
For your specific model here is what they provide:
https://support.hp.com/us-en/product/hp-envy-27-b200-all-in-one-desktop-pc-series/19390539 

In order to get access to specific technical documents you would have to go thought the HP certification program at: https://certification-learning.hpe.com/TR/benefits.html 

Thanks Wesley... I'll work on the certification.

Used to be they provided that info to the public, but many companies have stopped doing so because of  the "Opportunity Entrepreneurs" that infringe on what is considered propriety copyrights.
Explore the HP YouTube channel link I gave it is produced and maintained by HP.
Try the Hp Community: https://h30434.www3.hp.com/ 
On the HP website do a Virtual Chat they may provide the information to you.

You don't need certification, the upgrading and maintenance guide at https://support.hp.com/us-en/product/hp-envy-27-b200-all-in-one-desktop-pc-series/19390539/manuals tells you how to do it, you'll have to download and then add .PDF extension since somehow it is just called c05441224 rather than c05441224.pdf

The c05441224.pdf only covers the keyboard.and mouse. Not anything concerning the hardware as  they consider it copyright materiel.

Yes... I saw this. Didn't help.