I've never tried to model a car before, but when I saw your question, I thought, "Well that's a pretty simple one to answer". But upon actually trying it myself, I've found it to be a rather difficult thing to do. The best thing I can offer is to point you in the direction of the Boolean function. It's a hit or miss tool that sometimes works brilliantly and other times it just makes a mess of your model. It will allow you to subtract a cylinder from your model and in the process will cut a round hole straight through. You will then have to go in and extrude the hole and chamfer the edges. It's the curvature of the front end that makes this so difficult. It's going to be especially hard to keep the topology flowing smoothly with those two lights so close together. The result of my experiment is shown below. My topology's not that great, but I didn't spend a whole lot of time on it.