“Prioritizing” any data over another is referred to as “Quality of Service” or QoS
It’s hard to make suggestions about what hardware you do or dont need without knowing what you already have.
However, if you have any decent routers/switches already, THE best thing to do is ensure your voice/video traffic is on its own VLAN/subnet.
Yes, this will entail a touch of configuration of each and every device in the network, but without it your voice/video calls will be utter garbage
Provide a better glimpse of what make/model of network gear you are currently using, and we will be able to give you a more concise answer…