> There exist MiniSpec and Common Lisp Quick Reference for a beginner.

Not only that, but books. Common Lisp books going all the way back to the 1980s are perfectly, or almost perfectly usable, modulo some small issues due to CL not having been ratified until 1994.

E.g. Wilensky's Common LISPcraft [1986] (don't let the all caps LISP put you off) or Stuart Shapiro's Common Lisp: an Interactive Approach [1992]. Norvig's PAIP (the Lisp-based original) can be used for learning Common Lisp by advanced beginners.

Shapiro's book is out of print, but here is the free PDF: https://cse.buffalo.edu/~shapiro/Commonlisp/commonLisp.pdf

It is disingenuous to state that the only resource for learning Common Lisp is the HyperSpec, which is hard to use, ignoring decades of books, and tutorials.