Installation

sudo apt update
sudo apt install qbittorrent-nox -y

Set it up as service

sudo nano /etc/systemd/system/qbittorrent-nox.service

Paste (!!!WARNING: make sure your User=pi exists)

[Unit]
Description=qBittorrent Command Line Client
After=network.target

[Service]
User=pi
ExecStart=/usr/bin/qbittorrent-nox
Restart=on-failure

[Install]
WantedBy=multi-user.target

Enable and start the service:

sudo systemctl daemon-reload
sudo systemctl enable qbittorrent-nox
sudo systemctl start qbittorrent-nox

Try the WEB UI

http://rasbperrypi:8080 it should reside under that link.

Set up proper address bind to

In case application doesn't want to connect with outside world and no torrents are starting to download,
you have to update this option, and experiment what is best to make it work, in this case raspberry IP works