Use an SSH client like PuTTY to connect to the host using your root credentials.
If you are looking for this tool, you likely need to enable access to it rather than download a file. How to Access vim-cmd download vim-cmd
You cannot "download" as a standalone installer because it is a native, pre-installed utility built into the VMware ESXi hypervisor. It is a command-line interface (CLI) tool used to interact directly with the vSphere API to manage virtual machines and host services. Use an SSH client like PuTTY to connect