The pictures are poor but the wheel should be easy to remove.

Start by shifting to the lowest gear. Next, hold the long metal piece that ends the cable. There is a small nut on the assembly that, once snugged up, prevents the assembly from loosening off. Loosen that small nut a wee bit and then turn the longer metal piece in an anticlockwise direction. This will unscrew the longer piece, allowing the part that goes through the hub be detached from the control cable.

Now, loosen the wheel nuts and drop the wheel.