I spent the past 2 days in resetting my PC, and my main VPS too because I made the terrible mistake of not double-checking if my SSH keys for my main VPS were backed up. I had disabled root and password logins to improve security.
Fortunately, I took notes on how I set up software and apps on my machines, so I could quickly install everything on my VPS again.
Since I started to host stuff, including my websites, on the first VPS I rented, I have been learning to preserve my server's disk space as much as possible, including cleaning up unneeded files.
Today, I learned about systemd journal logs, and realised that they were the primary reason my VPS disk storage was taken up every day, so I configured /etc/systemd/journald.conf to prevent systemd journal logs from taking up more than a certain disk storage space (SystemMaxUse) and being kept for more than a certain time period (MaxRetentionSec).
This helped freeing up disk space of my server.