What exactly do you want to learn ?
Are you aware that to run what is called "a vSphere environment" or do you want to learn how to run VMs on a single ESXi host ?
That makes a big difference !
If you want to learn vSphere you need a VM with vCenter - that is another Linux VM that is used to manage several ESXi hosts.
If you want to learn how to work with a single free ESXi host then I highly recommend NOT to read any documentation right now.
Instead use your common sense and find out which files are required to build a VM - you will need WinSCP to make progress.
Unfortunately the complete VMware documentation is written for "vSphere" and great parts of the documentation does not apply to the single ESXi-host usecase.