https://www.golinuxcloud.com/run-systemd-service-specific-user-group-linux/

~# cat /etc/systemd/system/run-as-user.service
[Unit]
Description=Run service as user deepak
DefaultDependencies=no
After=network.target

[Service]
Type=simple
User=deepak
Group=admin
ExecStart=/opt/golinuxcloud/startup_script.sh
TimeoutStartSec=0
RemainAfterExit=yes

[Install]
WantedBy=default.target

~# systemctl enable run-as-user.service
~# systemctl restart run-as-user.service
~# systemctl status run-as-user.service