AxCrypt 2 works just like your email software or most other password-protected systems. You sign in once, and remain signed in until signed out. Just like you can read many emails without entering the password every time, AxCrypt will do the same. The files are still encrypted, but your password is remembered until you sign out of AxCrypt.
To share an encrypted file via email to someone else, you use the ‘share’ function in AxCrypt. You enter the recipients email address and the file will be encrypted in a way that the recipient can open it too. However, remember that the email address is just for identification (just like you sign in to AxCrypt with an email address). You still have to send the file itself to the recipient using your regular email software.