You have several ways to access vSphere components through vSphere interface options.

vSphere interface options include:

vSphere Web Client

The vSphere Web Client is a Web application installed on a machine with network access to your vCenter Server installation. The vSphere Web Client is the primary interface for connecting to and managing vCenter Server instances.

vSphere Command-Line Interface

A command-line interface for configuring an ESXi host.

See Starting and Stopping the vSphere Components for information and instructions about starting and stopping ESXi hosts and vCenter Server.