vent hood install

I have a food trailer I have been running for a few years,And have been moving my smoker outside at events and it's getting old when you do it solo.So I have been thinking about mounting my smoker inside.first question is:Can I just put a chimmey to the outside or is the HD going to want a overhead vent?
Second: How hard is it to install a overhead hood/vent system.I'm handy and have a shop full of tools.but I have never tried or seen how one is installed,are they mounted to the wall or the ceiling,do they have templates for drilling/cutting holes?are they any step by step photos of the process?