Partition Extender to extend system partition and data partition. No matter what disk map you have, Partition Extender will make it easier.
Extend Partition on GPT disk becomes a trend when Windows 10 anniversary upgrade comes. How to Extend Partitions on GPT disk without data loss?
How to shrink volume and make unallocated space so that partitions in low disk space status problem can be fixed?
How to redistribute disk space in Windows 10 when you don't have enough time to repartition or reinstall Windows 10.
Steps to free up disk space after Windows 10 upgrade, make more free space in system partition with Partition Extender
People would like to allocate more space to C Drive in Windows 10 after one year's using, how to do it with ease
Try to use Partition Manager Free Software for Windows 10 64-bit to extend partition, Partition Extender guides with screenshots in this page
Primary Partition is for running operating system, extend primary partition is to extend system partition when system performances poor
How to fix not enough disk space for Windows 10 upgrade problem? Add more space to system partition without data loss.
When Extend Volume option grayed out in Windows 10 Disk Management, you can use Partition Extender to extend volume.
Norton Partition Software for Windows 10 alternative partition software, Partition Extender, portable partition software for Windows 10 disk managing.