Get used to giving passwords in Linux. They are for your protection and the
reason why Linux is more secure than Windows. Any attempt to bypass them
weakens your security. You need to change your thinking when you move a new
OS.

Network manager does not ask me for my password, so I am not sure how you
are connecting to the internet. Some other network managers may ask for
passwords, though. Network manager shows the wireless networks in range when
I click on it and I just select the one I want from the list. If it is set
up properly it will have all of the information it needs to connect and
attempt to do so when you choose it.

If you want automatic connection you may want to consider installing wicd
(pronounced wicked) which is a daemon and connects before you even logon.