After successfully enabling the NVMe Tiering feature, which was introduced in vSphere 8.0 Update 3, you can find some useful details about your NVMe Tiering configuration by navigating to a specific ESXi host and under Configure->Hardware and under the Memory section as shown in the screenshot below.
There is quite a bit of information that we can see, so lets break down the individual items that are useful from an NVMe Tiering point of view and the specific vSphere APIs that can be used to retrieve this information.