autostart program on boot

In the terminal, edit inittab file.

sudo nano /etc/inittab

Disable getty:
find this line in inittab
1:2345:respawn:/sbin/getty 115200 tty1

And add a # at the beginning of the line to comment it out

add below this line:

12345:respawn:/bin/login -f root tty1 </dev/tty1 >/dev/tty1 2>&1
This will run the login program with root user and without any authentication

Step 1: Open a terminal session and edit  /etc/profile

sudo nano /etc/profile
Add the following line at the end:
. /home/startupscript.sh

make this script and do your stuff.