Log in to your Site24x7 account, and navigate to VMware > Virtual Machine. Click on any desired VM name.

The metrics that you view are your VM's occupancy in its parent ESX host.

Using Memory Utilization as an example, the value that you view from the VM monitor tab is the amount of the memory that the VM has used from what was allocated to it from the ESX/ESXi host. You can verify this from your vSphere console. For this, you have to log in to your vSphere console, and navigate to Navigator > Host > Virtual Machines > Your VM name > Monitor. 

Both the values viewed in the Site24x7 web client and vSphere console will be the same.

To view the Memory Utilization by the guest OS, you have to integrate your VM monitor with Site24x7 Server Monitoring.

With this integration, you can view VMware VM metrics as well as the Guest OS-level metrics in a single view.