Dragging either the king or rook for a 0-0-0 pieces keep snapping back into original squares. Help!

This is hard to explain.  I am very new to chess and to this site.  

Every time I try to perform (laptop) computer keyboard) either a 0-0 or 0-0-0 the pieces snap back into original positions.   Is there a special key on the computer I need to press to get the pieces to perform this move?  

Thank you so much!

Sailingpuntagorda

Are you trying to castle through ( or away from) check

Thank you for answering so quickly Lagomorhp!  

No.  I am not trying to castle through check.  Just simply trying to castle.  Thank you so much!

Sailing

cjxchess16 and LiBoat21

Thank you both for your instructions. Yes, I was trying to drag my king onto a rook.

 I shall try your instructions and do the g1 or c1 maneuver.

Thanks again!

Sailing

Really appreciate your help!