Yes if you surrender your seat in csab first round then you will get the refund of fee you have given for confirming you seat in josaa or fee for new registration in csab whichever applies to you. Also you should know that you will get the refund in the bank details you have provided. Note that you cannot withdraw after round 2 also after round 2 your seat is binding to you and you will not get refund from csab if you do not take admission in the allotted institute.