Help for finding ranges for WiFi Antennas

Hi! First up, a bit of background...

For a school project I am building a remote control submarine over the next year, similar to a FPV drone in the sense that it will have a video stream to the pilot (or submarine equivalent). Both the remote and sub will be controlled by a Raspberry Pi Zero, connected to a WiFi antenna each. I am controlling the system through WiFi, as it provided the best speeds, especially for the video stream.

I understand first of all that WiFi doesn't work underwater, I am well aware of that. I will make a float that will remain on the surface and among other things include an antenna to connect to the remote. The float will be connected to the sub by a cable.

My issue is communication between the remote and sub. I understand that 2.4GHz is my best option for range, so I think I will go with that. I am aiming to get at least 100m out of it. I am trying to work out what approximate ranges are for various standards (802.11ac, 802.11n ect.) and what effects the range of different antennas. I have tried googling and youtubing but I cannot get a straight answer.

Let me know if this should/can be asked anywhere else and I really appreciate any feedback.

Thanks

Edit: Or would I be better off just getting a normal USB WiFi adapter, and changing the antenna for a larger one