It is impossible to upgrade the CPU and RAM without shutting down the VM. For the storage it is possible to upgrade it without shutting down

o upgrade storage:
Log into the vSphere that hosts the desktop.
In the inventory view, right click on the desktop from the list of VMs.
Click Edit Settings.
In the Hardware tab, update the value for Hard disk to the desired amount.
Through the vSphere console, log into the desktop.
In Windows, click on Start.
Right click on Computer.
Click on Manage.
Click on Disk Management under Storage.
Right click on the disk you want to extend.
Click Extend
Follow the wizard to complete the extension.

It is impossible to upgrade the CPU and RAM without shutting down the VM. For the storage it is possible to upgrade it without shutting down

o upgrade storage:
Log into the vSphere that hosts the desktop.
In the inventory view, right click on the desktop from the list of VMs.
Click Edit Settings.
In the Hardware tab, update the value for Hard disk to the desired amount.
Through the vSphere console, log into the desktop.
In Windows, click on Start.
Right click on Computer.
Click on Manage.
Click on Disk Management under Storage.
Right click on the disk you want to extend.
Click Extend
Follow the wizard to complete the extension.