The normal force is a reactionary force given my Newton’s Third Law. Let’s say you have a block sitting on a table. The force of gravity pulls the block downwards, but similarly, the table pushes back with a normal force upwards. If the block isn’t moving, and the table is level, the normal force is equal in magnitude to the force of gravity and opposite in direction.
The friction force acting on an object is related to the normal force. More precisely, the friction force is equal to the normal force multiplied by a constant, called the coefficient of friction, which depends on the substances used (e.g. rubber on concrete, steel on ice, etc.). A different coefficient of friction is used depending on whether the object is stationary, sliding, or rolling.
If you have any questions, feel free to ask.