You've noticed your Shell is showing the wrong storage amount but you know you're supposed to have more. The issue here is likely due to unallocated space in your hard drive that's not being used or even recognized by your OS. Follow this guide to extend your (C:) Disk to use all the unallocated space! 

Delete the middle partition "Healthy (Recovery)"

1. Search up "Command Prompt" and run as administrator. 

2. run the following lines to delete the partition 

diskpart

list disk

select disk 0

list partition

select partition 3

delete partition override

You will see the following message when it has been successfully deleted:

Extend Volume (C:) 

1. Right-click the (C:) volume and select "Extend Volume"

2. Click "Finish"

3. Highlight Disk 0 and click "Next". The wizard will then close and your C volumn will be extended. 

You can confirm this by opening up file explorer and checking your drive! And that's it! Your Drive is now updated.