The folowing are the systemd units locations and content

nano /etc/systemd/system/tdarr-node.service

[Unit]
Description=Tdarr Node Daemon
After=network.target

[Service]
User=plex
Group=plex
#StandardOutput=null

Type=simple
WorkingDirectory=/opt/tDarr/Tdarr_Node
ExecStart=/opt/tDarr/Tdarr_Node/Tdarr_Node
TimeoutStopSec=20
KillMode=process
Restart=on-failure

[Install]
WantedBy=multi-user.target

nano /etc/systemd/system/tdarr-server.service

[Unit]
Description=Tdarr Server Daemon
After=network.target

[Service]
User=plex
Group=plex
#StandardOutput=null

Type=simple
WorkingDirectory=/opt/tDarr/Tdarr_Server
ExecStart=/opt/tDarr/Tdarr_Server/Tdarr_Server
TimeoutStopSec=20
KillMode=process
Restart=on-failure

[Install]
WantedBy=multi-user.target

nano /etc/systemd/system/tdarr-node.service

[Unit]
Description=Tdarr Node Daemon
After=network.target

[Service]
User=plex
Group=plex
#StandardOutput=null

Type=simple
WorkingDirectory=/opt/tDarr/Tdarr_Node
ExecStart=/opt/tDarr/Tdarr_Node/Tdarr_Node
TimeoutStopSec=20
KillMode=process
Restart=on-failure

[Install]
WantedBy=multi-user.target

Now to enable everything you can type the following. This will also start the services now because of the --now command

systemctl enable tdarr-node tdarr-server tdarr-web --now