I would download and install Automatic Surface Pro 3 virus removal tool to your Surface 3. Once it installs then you can follow the instructions on that removal. Make sure you malware is updated after that. That is the most easiest to do to remove a trojan on Surface 3. You can do it manually but if you are not sure exactly how to go about it, it could mess up your Surface 3.
There are many sites that have the removal tool so you would have to google it and choose which site you want to go with.