Realize OBS is free open-source software. So there is no formal support staff. Most folks here are users and volunteers.
With that said, there are many ways to get video input to OBS
A video capture device is typically required for a non-IP signal, for example, HDMI or SDI. USB cameras (which PTZOptics and others sell) can be directly connected to OBS PC.
For Ethernet/IP network based cameras, you don't need a capture device hardware (other than network interface connection ie LAN or WiFI port/connection). What you need for network-based video signal is software running on the computer to receive and decode the incoming video signal (ie, what protocol is used). Windows 10, from what I recall, can natively receive a RTSP signal, as long as no password is required (just silly, actually... basically worthless). So, what you are looking at is a driver that can process the incoming video feed. Some IP security cameras use cheap, low-performing/ high-latency chips, and use RTSP to send video over IP. With a decent camera, and a fair amount of hoop-jumping on your part, one can get decent performance using RTSP in OBS [I've read about others doing, so, I have not]. There is different software options to receiving a RTSP, with varying stability, performance, maturity, options, etc
The industry standard for low-latency video over IP is largely NDI. PTZOptics and others (Panasonic, Sony, Canon, etc) all have NDI enabled cameras (usually PTZ). I am a user of a Panasonic NDI PTZ camera. With NDI, there is an old, apparently no longer supported OBS plugin(?), and then the more common approach is via use of the free NDI Tools from NDI's author NewTek. With the Panasonic, they provide a VirtualUSB driver that takes the NDI video feed and makes it appear as a locally connected USB camera (to any Windows App that can use a camera, including OBS). Beware mixing camera video signal technology, as the varying latency will make audio/video sync a headache (and may well cost more than simply buying the same camera type). Low-latency can be helpful in avoiding audio delay setups to match video signal.
if you can afford it, and camera placement flexibility is desired, as well as single cable for power (PoE), control, and video feed, especially if longer cable run desired, then NDI is a nice-to-use approach. The Pro & Con is that OBS can then see each NDI camera input. That is a con as computer has to decode each signal, vs using a video switcher where only a single video feed goes to PC. So... it depends on compute power available, and your use case
I hope this is the type of input you were looking for