To determine if port 3389 is blocked, you can use a port scanner such as nmap to perform a port scan of your network. Nmap is a free and open source port scanner that can be used to scan your network. With a port scan, you can determine which ports are open, closed, or filtered on your network. To use nmap to scan your network for port 3389, you can use the following command:
nmap -p 3389
After the scan is complete, you will see a list of ports and a status for each port. If port 3389 is closed or filtered, then it will be listed in the results. Alternatively, you can also contact your network administrator to confirm if port 3389 is blocked.