How much throttle would you give normally for the quad to just fly from ground..?? I gave around 40% throttle.. But it didn't fly.. But my propellers flew away from motors..

Did they break and fly or did they fly away coz they were loose ?
If they were loose tighten them...

yeah.. what about throttle..?? from ecalc, linear throttle : 47%..

Based on the Motor Prop and LiPo setup that you have chosen and the AUW (All up Weight), the throttle % at which the quad will leave the ground will vary.
Let's go step by step.

Question #1
Did the prop break or did the prop adapter (the conical nut) just got loose and making the prop fly away?

Might be the prop adapter must be loose. Or if the props were of poor quality they could break even then..... Could be a case.
Most important, what is the type of motor, prop size, ESC rating, battery etc. I mean everything that is contributing towards the AUW of your quad should be known. Sometimes, due to more weight quad lifts at even higher throttle.
But, still the case with you is still a mystery untill we could know exact ratings of all the components. Is it any RTF kit available on various websites?