Cloudflare

How to configure Cloudflare CDN
How to Make Cloudflare work with Linode Webserver

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

read more
How to Add MX record to Cloudflare DNS
read more