Hi,

you do not need to reinstall the Prism Central, it is more or less the questions of ressource configuration.

Here you get an overview about the size and requirements:
https://portal.nutanix.com/page/documents/kbs/details?targetId=kA0VO0000002Dlx0AE

Than follow these steps:

1. Make sure the Prism Central cluster is stopped and the Prism Central VM(s) are powered-off. Refer to Shutting Down or Starting Up Prism Central VM to power off Prism Central VM(s) properly.
2. Log in to the Prism Element web UI where Prism Central VM(s) are deployed, and navigate to the 'VMs' page.
3. Select the Prism Central VM(s) that are to be updated.
4. Click 'Actions' > 'Update' and update the vCPU / Memory count as needed.
5. Proceed through the wizard by clicking 'Next' and 'Save' the new settings.
6. Start the Prism Central VM as describe in the Shutting Down or Starting Up Prism Central VM section.

unfortunately it is not as easy as it is mentioned in above post.
you might be able to change cpu and memory from the PC VM itself but for harddisk changes, you need to go to cli and do some changes.
if you have active support engage support and they will do it for you.
 

Which of the disk must be resize per CLI ? 

The disk scsi.5 needs to be increased from 100GiB to 500GiB. Having a single VM Prism Central and single vDisk you do not need to enter any command to expand the disk from my experience. If you do not expand the disk you will receive an alert from NCC check and that will provide a link to the corresponding KB about adding disk space by the way. Boot might take time and waiting to have all services up and running again as described in the articles.