I think a all-in-one wireless camera system works for you.
It comes with a monitor built-in recorder and 4 wireless cameras. Plug and play.
Something like this: https://www.amazon.com/dp/B09H6V7S7M/ref=emc_bcc_2_i
Do you have power outlets for the cameras? If there is no power outlets for the cameras, you need to go with either PoE system or battery cameras. While if there is power outlets for cameras, you can go with wireless system like above.