tried lcd /root/home/argo/Desktop, output was "couldnt change directory to /root/etc.. , no such directory or file exists. I am like super new to Linux.

Don't worry about it, but it would be a very useful idea for you to do some reading up on Linux basics. If not, to be honest, following online tutorials with a restricted idea of the underlying principles will cause you needless problems.

The directory you want is /home/argo/Desktop

/home contains all the users' home directories, except:
/root contains the root user's home directory

same error.
P.S I appreciate the help.

Is the error on the lcd command or the put command?

As you can't cut and paste, can you please write out the complete command and the complete error message, character by character?

Thanks.

Below are the commands i have used so far.
Initially with PUT command
----------------------------------------------------
sftp>put Desktop/index.html
stat Desktop/index.html: No such file or directory
----------------------------------------------------
sftp>put /home/argo/Desktop/index.html
stat /home/argo/Desktop/index.html: No such file or directory
------------------------------------------------------

Now the lcd command

lcd /home/argo/Desktop
Could'nt change local directory to "/home/argo/Desktop": No such file or directory

Ok, unless there is something very obvious that I'm not seeing (which is probably going to turn out to be the case), have you tried using the lcd command to go step by step to your Desktop directory?

i.e. (assuming ssh is pointing locally at /root)

lcd ..

lcd home

lcd argo

lcd Desktop

lcd /home --> worked
but after this i gave lcd /argo ---> same error, no such file or directory

Once you've got to /home, you want to do

lcd argo

not

lcd /argo

still same error

Ok, if you're still game to carry on,

Please tell me the results of:

lpwd

and

lls

After you've pasted this, don't do anything else with ssh until my next reply.

If you want to transfer a file from your desktop to the web server you do not need to login via ssh first. From your Ubuntu desktop you can use scp like below:

scp Desktop/index.html root@server:/www/var/html/index.html

You can also use sftp but again you want to run the sftp command from your Ubuntu desktop.

sftp>lpwd
Local working directory: /home

sftp> lls
sftp>

Ok, I'm really sorry that I was unable to help you. Thanks for bearing with me.

You should do as michaelk advised.