I want to search for a graphic card that suits my motherboard, but I don't know how!
For example, I have this motherboard, I don't know which type of graphic card should I search for.
How can I figure out what type of card I require?
You can use a site like PC Part Picker where you specify your motherboard and then will only show you CPU's, graphics cards, and other components that are compatible. You can also do some research about the specific motherboard and learn what expansion slots it has. After that knowledge is found you can research graphics cards based on the size of your case, size of your PSU, and support for PCI Express 2.0 or PCI Express 3.0. You can read more about PCI Express here.