It’s all new to me, not having a background in IT. I opted for the cleanest possible solution.
You didn’t have to reinstall everything, when you installed the headless server, you mistakenly chose the option to setup as LVM.
All you need to do next time is extend partition:
https://packetpushers.net/ubuntu-extend-your-default-lvm-space/
Here is a quick link to my tutorial to setup headless server.
Discussion
Yeah, don’t worry, the first time I installed Umbrel I did the same mistake and scrambled a few days to what was going on. Simple mistake you won’t make again 💪