There are innumerable types of hinges, doorcatches, locks and handles and it is impossible to give more than the barest outline about them.
Fortunately it is usually perfectly easy to see how to fit most of them.
The only point that matters with hinges is where the hinge pin runs. The door will turn about this point, no matter what the shape, size or position of the hinge leaves. Also, the hinges must be sunk into the wood of the door or the frame, or half in each, so that there is no gap when the door is closed.
Initially it may be found easier to sink the hinges into the doors, especially if they are covered in ply or hardboard. Simply removing a piece of this covering gives a suitable recess, though you may have to adjust the depth for very thin hinges.
For furniture, choose brass rather than steel hinges, with brass screws.
When mounting a door, screw the hinges fully in place to the door, with the hinge pins exactly in line with each other. Then place the door in its frame and mark the position of the hinges on this. Screw the hinges to the frame with only one screw each, if possible using a rather shorter screw than you intend to use eventually. Try the door and adjust the position of these short screws till it closes neatly. Finally attach the hinges to the frame tightly through the other holes, remove the temporary screws and replace them with the final, longer ones.
Catches usually come in two parts, the catch or striker itself, and the plate or socket to which it engages. Fit the striker first, nearly always to the door. You may have to make a shallow recess with a chisel to get it flush with the door frame.
Then close the door several times. The tongue of the catch will almost certainly make a clearly visible mark on the frame. This will help you to place the socket or plate accurately on the frame.