Hello I stored my username and password in session and cookie, but once users log out, I initiated them to be "gone." or blank.

My question is, is this secure to do that? also, I have a link that acts like this : http://localhost?username=(whatever the username in the cookie)&password=(whatever in the cookie for pwd)

I would like to get a short version instead of long link like that, plus I would like to hide that username and password information too. Can anyone help or provide insights please?