How to install an additional fan to my precision 3650 tower

I’m not sure if this is the best place to ask this, but I couldn’t find anything else online.

I’d like to know if it is possible, and if so, how, to install an extra case fan in addition to the already installed exhaust fan at the top of the chassis.

I can see there is a 4 pin connector on the mother board labelled ‘front fan’, however, on the chassis I cannot see any obvious screw holes or slots, but there is a large, fan-sized bit of dedicated empty space to allow the installation of an front fan.

Is there some kind of special way that a fan would just clip on? Because I can see a few little slots that look like they could be for screws, but there aren’t any screws already in those holes.

Many thanks.