Ahah! I think I found it.
It looks like a quite nice pc.
What is your intended use?
Here is what I would do.
1. I would replace the installed HDD with windows on it with a Samsung 860 evo of whatever capacity you want. A ssd will use the same power as a HDD, perhaps less.
The power used is minimal if you want to add one.
A ssd will transform the performance of anything you do.
You open up the case and attach the ssd using one of the blue sata ports on the motherboard and use the sata connector which I see.
I think you can do this with the case open, but if you want to close it, just leave the ssd lying on the bottom. When done, replace the current HDD with the new ssd and test.
It looks to me like the current HDD is a 2.5" drive so the replacement should be compatible.
2. In the event that you want to do some gaming, you are limited by the 230w available on the power supply.
The card must also be low profile to physically fit.
I might suggest a GT1030 card like this:
https://www.newegg.com/evga-geforce-gt-1030-02g-p4-6333-kr/p/N82E16814487347
The card does have a fan, and it will direct the heat out the back of the case.
3. There are no fans supplied, and no places to put one.
The cooling needs are minimal, and depend on convection.
The only fan is on the power supply.
It draws air from the interior of the case and exhausts it out the back.
This is sufficient for the cpu installed.