Something more like this https://a.co/d/0bgPCSvQ - it should use half the power, it’s way smaller, 2x SATA if you want 2 drives. I haven’t checked if this specific one is 12V, but there are dozens in the same form factor and with similar specs.
There are a lot of atom or mobile i3/i5 powered mini PCs that actually are powered with a 12v brick, in fact most of the industrial ones are. Small form factor, passive cooling, can play media for you and usually comes with 4x 1/2.5gbit Ethernet, so it can double as a router/switch. Usually 10-15w power draw.
Go to AliExpress and simply search for minipc and make sure it has a SATA connector for your hard drive.
Budget (about 200 euro):
Better(400-500 euro):
TP-Link omada line is basically a bunch of ubiquity clones at much lower price
See 2nd half of the post for some tips.
I’m going to echo what some others said: medication is usually effective and often so much so it feels like cheating. I know you’ve mentioned it’s impossible to get it where you live, but it’s very likely you are wrong about it:
Several years ago I moved back to my home country (Poland) only to learn that according to local regulation there is no such thing as an adult with ADHD. They reluctantly admit that ADHD exists, but only as a childhood condition. On top of that most doctors don’t like or straight up won’t prescribe anything psychoactive, even antidepressants. It took me a while to find a doctor that would prescribe me the meds I need, only to learn that what I was taking for years was not available in the country, so every 3 months I’ve had to go through entire target import procedure to get 90 days worth of pills.
It’s hard to get those meds in many countries, but people who need them and manage to get them share their experiences. Do some searching and you might find some help.
General tips:
Working at a desk/on a computer: