Hi folks, I recently got my hands on some free drives, and put together the attached list (combined my OG \~2015 drives + the "new" hand-me-downs) to decide on which ones to keep for myself and which to give away to other people who might need them.  
The 2TB HDD Spinpoint (red) I'll probably pass on, as it's super old and I don't know if it's worth the hassle. The Toshiba SSD (orange) is an external drive, but I'm happy to break it out of the enclosure and get some Micro-B to SATA adapter for it?

So, I've started thinking about putting together my first home NAS, with the following use cases:  
\- shared storage for me & family (+ backup or RAID)  
\- adblock - I currently have AdGuard dns on my router, but would prefer a more robust solution on the NAS (Technitium?)  
\- media streaming - I'm currently using Plex on my PC, but would prefer to have it here (as long as the NAS can handle streaming 4k videos). Can stay on Plex or move to another app (Jellyfin?)  
\- down the line would probably add some Smart Home features, especially cameras.

Now, I'm not a total tech noob - I put together and fixed my and other people's PCs since I was a kid in the 90s, so I know my way around a MOBO; however, I have never used a NAS, or had to setup and use containers, etc. so I'll have to learn how to setup and configure everything.

Can you help me decide which of the drives to keep to use for my use cases?

Another thing I need help with is to decide if I should go with 2 separate devices, so for e.g. use the 2x4TB drives in a simple 4 bay NAS for storage (empty bays for future expansion) for backup and media streaming, and have another device with the SSDs for adblock, Smart Home, etc.?  
Or just do everything on the same device?

One last thing, since I'd like for it to be as SFF and energy efficient as possible, so I'm happy to jerry rig something, or go with a miniPC+4bay solution, etc.

NAS for a newbie