What is the overall goal in asking this question?  ESXi is based on a Linux system, so it will load similarly by starting the bootloader then switching over to the kernel.

Any issue booting a ESXI?  stuck during a specific state ?

Hello,

Thank you for your reply.

So, when does the BusyBox and VMkernel run?

BusyBox is a small binary that runs in the shell and provides standard functions such as ping, vi, nslookup, etc.  VMkernel is an application that runs at startup.

Hello,

Thank you so much for your reply.

Can you show me a diagram which shows the components that are executed in order?

hello, you could probably find interesting infos at the following link

https://www.vmware.com/content/dam/digitalmarketing/vmware/en/pdf/techpaper/ESXi_architecture.pdf

I haven't seen that doc in years!  I do have to wonder, how much has changed?  I think the general picture is unchanged though, so should be good for OP's needs.

BTW, why are you needing this level of info, if you don't mind me asking?

Hello,

Thank you so much for your reply.

I want o learn it deeply.