Hello,
there's no problem with that. I have also an account in Linode, so I have experience not only in SSH/SFTP.
I will configure in your linode with sftp, configure iptables to permit connections to port 22 if it isn't already configured, and I can also configure this account to be SFTP only (he will only be able to do SFTP transfer, but not having access to bash shell) if you want. I can also configure this account to be authenticated with a private/public key pair.
I can also teach you how to do the transfers, with a windows client or a linux client.
I've done it hundreds of times, so no problem doing it, or teaching you how to do it.
Regards