sytemd xvfb

xvfb.service

[Unit]
Description=X Virtual Frame Buffer Service
After=network.target

[Service]
ExecStart=/usr/bin/Xvfb :1 -screen 0 1024x768x24 -ac +extension GLX +render -noreset

[Install]
WantedBy=multi-user.target

you can also templatize the :1 value so if you wanted to start up lots of different servers

copy this file into /etc/systemd/system/xvfb.service

then run

sudo systemctl enable /etc/systemd/system/xvfb.service

then to start xvfb run:

sudo systemctl start xvfb.service

and to stop xvfb run:

sudo systemctl stop xvfb.service

Will this script autorun at system startup if I enable it as service?

no I believe in order to do that you should use the command
sudo systemctl enable xvfb

For reference, here is the /etc/init.d version https://gist.github.com/dloman/8303932