Discs replacement and clunky noise at the front

[Eban1969]

Hello everyone,my mum has a little jazz 1,4 auto 2005/6. First, when replacing the brake pads do the caliper piston push in or do they need to be screwed back in.

Second, clunky noise when turning left,more when turning rather than sweeping left on a curve, garage doesn't know what the problem is,but have my doubts about said garage.

Thanks in advance for any replies 

Regards Eban