Oh what an oversight!!! Samantha, many mfgr's use a spring loaded "stay opens" that attach to the cabinet frame and to the vertical edge of the door. It's a tube shaped gizmo with a spring loaded piston inside that helps lift the door and hold it open when it's extended. Home Depot and Lowes may have them in the cabinet and kitchen door furnishings. Alternatively, they will certainly be at a good RV supply store. Depending on the size of the door it may take one on each side.
Simple one hand operation... Open door and it stays open. Inexpensive....
There are also some "positive closers" that will keep door closed. They are spring and roller devices that attach to the upper horizontal edge of the door and cabinet frame.
Use care when installing so you don't drill through the door! When installing them.