Is it normal that front wheel bends when front disk brakes are applied? When I apply front disk brakes I see slight bend in the rim and wheel. Is this normal or I have a low quality parts.
No, not normal at all. You should have a bike shop look at it for a safety check if you are new to the sport and bike.
One thing that can cause a wheel to bend is poor spoke tension. A good bike shop should be able to fix that for you pretty quickly.