I'm going to assume you mean Syncovery-10.16.11-amd64.deb, downloaded from this page.
What exact are you expecting to find? It's not really a desktop program with a graphical interface, as stated in the documentation:
These include the Web GUI and install and start the service automatically. The internal web server listens to port 8999. Do not use this on a server that is directly connected to the Internet. Use it only behind a router within your LAN.
After installation, open the Syncovery GUI by visiting localhost:8999 in your web browser.
If you want, you can create a shortcut yourself by following the steps outlined in this post:
You just have to adjust the values accordingly.