Hi @Amr.Magdy ,
if you want to wipe your drive, you can use Gparted which is included in the Live Ubuntu CD/USB image, or download a full ISO from the following link!:
http://gparted.org/download.php
If you know little about partitioning, please start here (UEFI info at the bottom of the guide with links!):
PLEASE NOTE: THIS GUIDE DOES NOT DEPICT THE INSTALLATION (CREATION) OF A UEFI PARTITION. IF YOU HAVE A COMPUTER WITH UEFI/BIOS, MAKE SURE YOU ALSO CREATE A UEFI/BIOS PARTITION AS WELL. SEE FURTHER REMARKS ABOUT UEFI PARTITIONS IN THE GUIDE!.
Linux beginners should also look here:
You can only partition on an unmounted drive using an installation disk of your Linux flavour with a partitioning tool included, use the Gparted tool in live mode, or you can download a copy of Gparted from the link…