My battlestation, any suggestions? [WIP]

I primarily work from home and want an external setup that improves my video quality and docking experience.

1) I’m looking for a high-resolution webcam (ideally 4K) compatible with macOS and Windows, for Zoom/Teams video calls.

2) I want a dock for my MacBook Pro so I can use it closed (clamshell mode) and still connect displays, USB devices, and peripherals.
I’m currently using an HDMI splitter between my PC and MacBook and want a solution that plays nicely with that setup.

3) Is there a splitter I can connect 3 HDMI for my PS5?