Yes, you can open all ports in your router. In order to do so, you first have to access your router’s WebUI. Next, go to Network -> Firewall -> Traffic rules. Scroll to the bottom of the page, where you will find a section Add new instance. Here you need to select an instance type as Open ports on router, enter any name, choose the transport protocol and enter the port range 0 – 65535, finally, press Add. A configuration window will open where you can specify more details regarding the rule: source, destination IP and MAC addresses, action to be carried out in case the rule is matched, etc. Once the rule is saved, you might want to check if none of the above rules contradict your setting since rules are checked sequentially, by the way they are ordered, and if a rule is matched with the incoming packet, no further rules may be processed. Just drag and place it in accordance, and press Save & apply.
You will find more details on configuration options in this website: