The most reliable way to transit data (assuming you don’t put a digger through it) would be fibre optic cable. I believe you can direct bury fibre optic cable with a piece of farm equipment, so might be something you can rent or borrow from a fellow farmer. Ethernet is not a great option because of distances and grounding.
Another option would be use a point-to-point wireless system. I believe UniFi sell these. They’re not too expensive, but wouldn’t ship anywhere near as much data as fibre.
Assuming you mean networking/Internet, then the job is done. Some switches on either end and you should be sorted. But if you actually mean WiFi, then using a wireless system would be best. Something like UniFi or TP-Link Omada would be good options.
Only change I’d make is to run Debian on my server over Ubuntu. I’d still run everything in Docker Compose rather than something else, or consider the use of something like k3s.
The server setup to get it ready for hosting data was a bit complicated, so I liked someone’s suggestion of putting everything in an Ansible playbook. I’d consider doing that.