Failed to run Jellyfin

[yasaitori]

I use my android phone to run Jellyfin. That means i used the "termux" to run an ubuntu system.
Then I can't run it normally.
https://www.helloimg.com/i/2024/10/02/66fcc817175d2.png
I can't use service jellyfin start

[TheDreadPirate]

Systemd is not installed or was not enabled in the boot settings.

https://wiki.ubuntu.com/systemd#:~:text=...n%2C%20the