Generally follow this
Create Origin Certificates:
Next page leave as default and click Create:
Make two files locally on your computer:
Upload the files to your Linode server using Filezilla:
Follow the appropriate tutorial for adding SSL to the linode server Fromhere and from here
To SSH into the Linode server need to follow this and download Putty from here
Install and start Filezilla Press Ctr+S Keys to Connect
More here