Hey i was desinging a buck converter using LM2576 IC.
i have two questions:
1. More Capacitor at input and and output means better, Right ? currently there value are 100uF and 470uF respectively.
2. What should be the value of inductor, i was thinking of 330uH

 

The datasheet gives the details of the calculations necessary for the values of the inductor and capacitors.

 

1. More Capacitor at input and and output means better, Right ? currently there value are 100uF and 470uF respectively.
2. What should be the value of inductor, i was thinking of 330uH

No, more is not better for a switching regulator.
If you deviate significantly from the values calculated from the data sheet equations, the converter may become unstable and/or not work properly.