His explanation was very good. With it and with the help of the other members of the forum, I am beginning to better understand the use of PROGMEM.
I do often use a buffer. For example for libraries that do not support pointers to PROGMEM
I'm redoing my sketch and this logic is the one that seems easier now. But faced with something you said before and testing that I did, I had a question. You said:
You can put char arrays and tables with pointers in flash memory. That is normal.
All char arrays saved in flash need to be contained in a table of string pointers so they can be processed by commands like strcpy_P or strcat_P?