how to install DraftSight.deb cad package

Hi,

I am trying to install DraftSight, a program that views Autocad files.

I have a Inspiron 1720 laptop.

I downloaded the draftsight.deb file many times, however, I can't seem to get it installed. I can't find a way to convince Synaptic Download Manager to see it, and I have tried to manually install via the Terminal. Here is what happened:

darcy@darcy:~$ sudo apt-get install draftsight
[sudo] password for darcy:
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package draftsight
darcy@darcy:~$ sudo apt-get http://www.3ds.com/products/draftsight/download-draftsight/draftsight.deb
E: Invalid operation http://www.3ds.com/products/draftsight/download-draftsight/draftsight.deb
darcy@darcy:~$ fuck you too!
No command 'fuck' found, did you mean:
 Command 'suck' from package 'suck' (universe)
 Command 'fsck' from package 'util-linux' (main)
fuck: command not found
darcy@darcy:~$ ^C
darcy@darcy:~$ ^C
darcy@darcy:~$ sudo apt-get install draftsight.deb
[sudo] password for darcy:
E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable)
E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?
darcy@darcy:~$ i don't have a fuckin clue
>

Please excuse the expletives.....

Thanks for your help.

Darcy