how do i expand space for drives for example (C)?

Hi! If you created a new partition by taking space from C: and now want to return that space, the official method is to use Disk Management: Press Win + R and run diskmgmt.msc, locate the partition you created next to C:. If you don’t need the data on that new partition, right-click the new partition > Delete Volume (this erases the data and turns it into Unallocated space), then right-click C: > Extend Volume to add the unallocated space back to C:.

If Extend Volume is greyed out, it’s usually because the unallocated space is not immediately to the right of C:, Disk Management can only extend a volume into contiguous unallocated space directly after it.