If you want to have (recommended) the 450 MB (UEFI-GPT) or 500 MB (Legacy BIOS-MBR) System Reserved partition in addition to the Windows C: partition on a HDD or SSD after installation, then you would need to make sure that all partitions on the drive have been deleted until it is only unallocated space. Next, select the unallocated drive to install Windows on. If there are no partitions on the disk, you will get the System Reserved partition.
If you do not want to have the 450 MB (UEFI-GPT) or 500 MB (Legacy BIOS-MBR) System Reserved partition and only the Windows C: partition on a HDD or SSD after installation, then select a formatted partition or drive to install Windows on. If there are any partitions on the disk, you won't get the System Reserved partition.