A drywall guy
It's not that hard, but the learning curve is long so it depends on how much time you want to spend on it. Shouldn't be too expensive
If you want to do it yourself, I recommend reading up on it in The Old-House Journal. You can look up any topic in their index and find just about anything dealing with repairs of an old house.
However, if you prefer to hire someone, I would not hire an electrician to repair holes in plasterwork because their job is to make the holes, not fix them, Instead, if the ceiling is genuine plaster, as it appears to be in the photo, then you need to find a plasterer/dry wall man who has experience working in plaster repairs. Not everyone does.