How to install Skyrim Realistic Overhaul for Skyrim Special Edition?

I have downloaded:

Skyrim_Realistic_Overhaul_Part_1.7z
Skyrim_Realistic_Overhaul_Part_2.7z
Skyrim_Realistic_Overhaul_Part_3.7z

From:

https://www.moddb.com/mods/skyrim-realistic-overhaul/downloads

According to the installation guide:

Installation:

-Extract data folder into your Skyrim installation and overwrite. 

I need to copy the extracted data folder to my Skyrim Special Edition data folder.

Now when I open my data folder in my Skyrim SE installation location I have:

After copying the content from the 3 archives I now have a textures subfolder:

and I did not get asked to overwrite anything - since there were no textures folder before doing the copy.

Content of the textures folder is:

Now I start Skyrim from Steam as I usually do but the game looks exactly the same as before. So the updated textures are not picked up.

What am I missing here?

UPDATE:

I think I managed to get it to work using Mod Organizer and this video:

My Mod Organizer configuration:

And some screenshots:

Not really sure why the kids head looks like its on fire but beside from that something looks a bit smoother.

Also regarding the C:\Users\user\Documents\My Games\Skyrim Special Edition\Skyrim.ini file it currently contains:

[Archive]
sResourceArchiveList=Skyrim - Misc.bsa, Skyrim - Shaders.bsa, Skyrim - Interface.bsa, Skyrim - Animations.bsa, Skyrim - Meshes0.bsa, Skyrim - Meshes1.bsa, Skyrim - Sounds.bsa
sResourceArchiveList2=Skyrim - Voices_en0.bsa, Skyrim - Textures0.bsa, Skyrim - Textures1.bsa, Skyrim - Textures2.bsa, Skyrim - Textures3.bsa, Skyrim - Textures4.bsa, Skyrim - Textures5.bsa, Skyrim - Textures6.bsa, Skyrim - Textures7.bsa, Skyrim - Textures8.bsa, Skyrim - Patch.bsa
bLoadArchiveInMemory=1
sArchiveToLoadInMemoryList=Skyrim - Animations.bsa