You can do that with pihole and basically any reverse proxy. The process is the same, so you can follow tutorials, you just have to set up your domain through your pihole instance instead of a registrar. You can set pihole as your dns for specific devices, or you can set it as the default dns for your network through the router.
Did you have to use a display to flash? Some of them don't seem to have a display output and I don't know if that will be an issue. The apple thing concerns me. There are a few macs and iPhones on the network, but the macs are m1, and the oldest iphone would be a 12. Do you think that would be an issue? Also, which R3 router are you using specifically?
They said they want a local backup so they don't have to redownload because bandwidth is expensive. I think a RAID makes more sense. I also don't think btrfs is a great idea for a boat. Power failures will probably be somewhat common, and btrfs is not the most stable, so I don't think I would trust it in weird conditions. Documentation is definitely a great idea though.
For hardware, I would go with sata ssds for storage. I also would recommend a separate boot drive as it makes re installing without loosing data a breeze. You could go with a new processor from intel or amd, and make sure it has onboard graphics. You should also go into the BIOS, enable xmp (always do that. It's free performance), and look for power saving settings. You could go for arm, but most arm computers lack expansion options and that can mean you use USB for drives which is unreliable. I think dc atx power supplies are a thing, but I know nothing about them. I would recommend doing ext4 and a raid, ideally 6 or 10. That will give you stability (from filesystem issues) and good reliability. I know RAID is not a backup, but in this case it may be what you want. RAID is for uptime, and it would be able to usually buy you enough time to finish your trip, or you could even have spare drives onboard and fix it while you're out in like 10 minutes. Also, I would highly recommend researching how to power it well. Starting an engine can mess with the power and could fry a computer. I don't know if a dc ups is a thing, but if it is, get it.
For software, use whatever you want, mostly. I always use debian for servers, but proxmox would probably be fine. You can use powertop to make sure it runs efficiently.
You can. I am lucky enough to not have been hacked after about a year of this, and I use a server in the living room. There are plenty of guides online for securing a server. Use common sense, and also look up threat modeling. You can also start hosting things locally and only host to the interwebs once you learn a little more. Basically, the idea that you need cloudflare and aws to not get hacked is because of misleading marketing.
I know i2p is a bit hard, but if you can figure out how to torrent you should be able to. I would recommend i2p+, which is a fork of i2p that is compatible with regular i2p but is easier to setup. Get the installer here: https://i2pplus.github.io/. If you are on linux, don't worry about it being an exe, it is java and you can run it with "java -jar file.exe." After that, you can open a browser and type localhost:7657. Set your proxy in your browser to localhost:4444, for the http and https settings. It may be different if you use chrome. Now you should be able to access tracker2.postman.i2p/. Don't forget a slash at the end. Your browser won't recognize it as a website without it. You will need the torrent client, i2psnark, which can be accessed on localhost:7657/i2psnark.
This may sound complicated, but the steps to install i2p boil down to:
I think the teacher specified that we use eclipse, and most who didn't were using vscode. If I recall correctly, they did use eclipse. I don't remember how it handles saves, but I don't think it does that.
Gen Z here. Totally agree, though I personally am a bad example for this one. There was someone in my CS class once who I was put into a group with for a project. I needed some code that they had, so I asked them to put it on my flash drive. It was taking a while and eventually I asked why. They didn't know where their IDE saved their code, and were using Windows search to try and find it. They were pretty good at actual programming, logic, etc. though.
Openhab is a project like HomeAssistant. Both are basically websites that offer pre made smart home functionaility and can run on your own server. Openhab doesn't set a password by default (iirc), and when people expose it to the internet they end up with random bored people in another country somewhere flipping their lights on and off or adjusting their thermostat, though they could also get hacked. The openhab example was one of what not to do. I could have been more clear about that.
Security is an issue that people in this community are fairly opinionated on. Try to build up a practical knowledge of every tool you use (like tools for remotely managing your server). Think about how much access that tool gives you, and how easy it is to get. Ssh gets you basically full access to the system, except for bios level settings and things, but it is generally quite secure, and you can use keys instead of passwords. Cockpit, a remote management tool you can access from your browser, offers you a full terminal, so functionally the same access as ssh. However, hackers nearly got a back door into openssh (ssh is the protocol, openssh is the software on linux that implements that protocol), and cockpit is much less thoroughly looked at. Also cockpit doesn't let you use keys.
Edit: This one is good too. I recommend at least skimming it before the one above this. It will help you figure out which of the points in the link above are worth paying much attention to. https://owasp.org/www-community/Threat_Modeling
To be fair, Netflix and the others all had to pay licensing fees and whatnot. I think governments should simply ban exclusivity deals so that competition can exist.