First thing to do is to check your fuses.

 

Did all the blinker fluid leak out? JK... Check the fuse.

 

I have the solution.

 

Are both brake lights out? i had that on my 2018 crewcab. I found a bad wire in the harness where it runs to the back, between the rear wheel and the back door on the right side. There is a connector and then the harness wraps over the top of the frame and comes too close to the exhaust, and I think that is where it broke the wire. I ended up running a new wire from further up front to the back and moved the harness to the side so it is further from the exhaust.