Photen,
I am also new the ESXi server game, and had the same issue. What I discovered was that if I left my machine running, the admin console via HTTPS would come up to a point where I could log back into the machine remotely. From there, I went to Host > Manage > Hardware, and selected my video card (Intel HD 620), and clicked "Toggle Passthrough" to turn GPU passthrough back off.
After rebooting the host again, the main boot screen processed to completion and no longer hung, finishing on the page displaying the hostname, IPv4, and IPv6 address of the host as normal.
ESXi Server Version: ESXi-6.7.0-20190802001-standard
GPU: Intel HD 620 Integrated, i5-7500T
Maybe too late to help you now, but hopefully helps future visitors confirm the issue is related to using the GPU passthrough functionality.