Establishing a priority route between a Netgear M4250 switch and a router

A neube here. I am setting up a new install for live streaming at a church and have installed an M4250 to manage things. The configuration is that I have 4 ports assigned as NDI and they do not need to see the Internet except for firmware updates. I want them to act basically as a separate network so that the traffic there does not conflict with data traffic elsewhere on the switch. Those ports have been configured for NDI5 using the supplied configuration app.

I have one port that connects to the stream encoder and I want that port to connect to the building router and on to the Internet. I want that route to have priority over all other data and Internet traffic on the switch. Also connected to the switch is the building WiFi through which all phone and tablet traffic will travel. I want to make sure that the encoder stream has priority over all the other general traffic on the network.

I have never configured a managed switch before and am attempting to understand how it should be configured and learn the structure behind all of it. Any help will be appreciated.  .