There is no bolt or screw to remove.
The headlight simply pops off. If it hasn't been removed in a while, it is going to be hard to remove, but it will come off.
Just grab the bottom of the housing with your fingers and snap it toward you. The bottom will pop off. Then you can snap the top off. It's held on by three snap fit ball and socket connectors.
Here's a helpful hint... Apply a this coating of lithium grease to the sockets before replacing the assembly.
BTW, why do you want to remove the housing? It's not necessary if you are needing to change the bulb...