Hi
I assumed it was a new un used hard drive when windows vista or latter creates a small hidden boot partition and uses rest for windows c: partition
If it had existing partitions windows it may offer to format one and install windows there
If you start again , take advanced option to remove all existing partitions, then create new partition using all of SSD
Back up any important data before proceeding
If you also have a hard drive remove it or disconnect to ensure windows is properly installed on SSD
Regards
Mike Barnes