how can i get webroot Internet Security complete plate to download on my tablet?

Hi nitajo44,
 
Welcome to the Webroot Community.
 
I'm assuming your tablet is Android based. If not, please let us know.
 
To do this I recommend installing the Free version of Webroot Mobile available HERE, and then registering it with yor keycode, which will then upgrade your Mobile version from Free to Premium. You can find directions to do that HERE.
 
If you're still having trouble then please let us know, or if you'd prefer you can submit a trouble ticket so Webroot support can check this for you. This is a FREE service with a paid subscription.
 
Please let us know if this resolves your issue. :)
 
Thanks,
BD