Thankfully, with a modern minibuffer UI package (Ivy or Vertico, for example), we don't need to remember arcane key bindings to run rarely used commands. To run such command, just run M-x and enter a substring of the command name. This video (posted here months ago) explains this topic very well.
For Emacs's help system (Info), I recommend to try C-h R info
.
You can get 50 items at most with
limit=50
. Try