Hi Ramya,
I am Dave, I will help you with this.
1
Windows should be running form the C drive, there should be no issue seeing that, if you open File Explorer, then click 'This PC' on the left, do you not see your C drive on the right?
2
Open Disk Management (accessible by right clicking your Start Button)
Resize the bottom pane so all drives are visible in that pane, then please provide a screenshot of that Disk Management window.