My name is Nesim and I am here to try and help you out with the question you might have.
First of all if you want to secure your remote desktop connection you should be using one of the premium VPN's
and nowadays there is literally ton of them. But the one I highly recommend is "ExpressVPN"
It is very flexible and you could find yourself doing multiple things with it right.
Also if your using windows 10 make sure your windows defender is set to defend you from any viruses or potential threats and your good to go.
But if your not using windows 10 I highly suggest using AVG antivirus which is the most amazing one I ever stumbled upon (even though I am not using it anymore since I use latest version of windows 10 with it's own windows defender now), but earlier I was only using AVG for those kind of things.
Hope this answers your question,