Hey guys about to pull the trigger on a 2016 IS F sport however it is Lexus certified pre-owner. If I want to add fog lights to them would it void my warranty? What I mean by that is, if I install fog lights but then need to bring the car back to the dealership, could I just take the fog lights out beforehand? Or would they know and then void my warranty?

First, installing/removing the fog lights requires removing the front bumper...so I doubt you'll want to remove them after you do the install.
Second...only if the fog lamps cause an issue with the vehicle, then the dealer could void the warranty for the item that was damaged by the fog lights...not the entire car.
If your IS is prewired for fogs, then you could install an OEM light control stalk switch that already has the fog light switch in it...and the fogs would be a simple plug and play behind the front bumper.

I just purchased a 2016 IS F sport, but I don't think that it is prewired for foglights. Do you have any video tutorials or guides on how to install the fog lights? Do you also have any recommendations on fog lights? I prefer the clear/white color, and I'm trying to do as much research before I start this process.

specONE made a good video for installing a winjet kit:

The way I have my winjet kit wired is a control + signal wires routes through the firewall by the footbrake into a blank button.
Signal wire tapped to a ACC fuse, and the control wire+button go into a blanking plate under my BSM switch.
Power and Relay harness which was supplied is run to the battery, keeping it close to existing wires and away from the heat
Ground was attached to a bolt somewhere.

I chose the winjet kit because you can pick your own bulbs, I have phillips extreme vision led bulbs in mine.
I think there's also the ijdmtoy kit, but they have built in led bulbs.

I have the Winjet kit with the LED bulbs. Spec's video is pretty much your goto for install.
My IS was prewired, so I installed the OEM stalk switch, which isn't hard if you're comfortable with taking off your steering wheel and all the little bits behind it...at that point it's also plug and play.

There are some really good threads here about installing the foglights. trickiest part is feeding the wire through to a switch. You can also do the stalk if you're one of the lucky ones with it prewired.