Unisync should be installed both locally and remotely. You will then run the local copy, and it'll connect to the remote copy. Please select your Operating System above to see installation instructions for it. For example, if you're on a Mac laptop connecting to a Linux VPS, you would follow the Mac instructions for your laptop, and then SSH into your VPS and follow the Linux instructions to install it there.
Since this is a command line tool, let's download it from the command line! We're going to create a folder for it and put that folder in the PATH, but that's totally optional.
mkdir C:\unisync
cd C:\unisync
bitsadmin /transfer unisync "https://unisync.sh/download/windows" "C:\unisync\unisync.exe"
Now let's add our C:\unisync folder to your PATH. Select Settings from the start menu, and type "environment variables" into the settings search box. Select "Edit environment variables for your account" and add C:\unisync to the PATH.