@pikebooo,
Quote:I still don't understand... how the cryptograms works
In a cryptogram every letter has been substituted for another letter. In the one you provided, each time the letter N appears, it has been used instead of an I.
The letter a is used instead of an L, m instead of o, o instead of v and so on. The coding remains uniform in any particular cryptogram, however the same coding may not be the same for another cryptogram..
In other words, the puzzle could have appeared with G tfhm zfq instead of N amor kmi.
The starting point for me is to go to one letter words. This reduces choices to the letters a and i. Once that is done the other letters begin to fall into place. Always keep a sheet of paper on the side listing the letters as you figure them.
There are several sites on the internet which will offer instructions on how to solve. Just do a google search.
Here's one:
https://cryptograms.org/tutorial.php
and another:
https://m.wikihow.com/Solve-a-Cryptogram