It stucks there, and I can’t do anything about it.
(post deleted by author)
It can take a long time for Unreal Engine to load certain content for the first time, such as at the 45% or 74% progress stage.
You can open Task Manager to check which processes are consuming most of the CPU, and see if any new processes have launched (these processes will terminate once their tasks are finished).
The progress display will show what content is currently being processed, and you can troubleshoot issues based on the text displayed there.
Usually you only need to wait, which may take a few minutes.
For reference only.