Your bike is not designed for a rear rack, so anything you add will be a bit of a kludge. A touring or commuting oriented frame would have rack/fender mounts on the rear dropouts and near the seatstay bridge (your frame does not have these mounts. The holes you see are for disc brakes.)

The easiest solution is a seatpost-mounted rack. It won't hold as much weight, but should be fine for commuting.
https://www.rei.com/product/743341/t...e-frame-e-type