It is never sent to a server, never stored.
Web Crypto API · no network request · nothing stored
The requests made while the page loads have nothing to do with your password. No additional network request is made while a password is generated.
What is entropy? It shows how hard the password is to guess. As the bit value rises, the number of possible combinations grows exponentially. In general, under 40 bits is considered weak, over 70 strong, and over 100 excellent.