The laptop should have been supplied with a Recovery Disk (CD). You will probably need to boot from this and install the OS plus whatever else is there to bring your laptop to the condition it was when it left the factory. This is for a Toshiba but it should be similar to your laptop click here
The next job will be installing all the security software you had previously and updating it, followed by updating the OS. After this comes all the other programs you had installed and any updates, followed by any backups of data files you should have made.
It would have been far easier if you had used Acronis True Image or similar to make a backup on an external hard drive. That way you could have booted from the Acronis Emergency CD and installed the backup image to your new drive. This would have left you losing only the data input between your last backup and the failure.