You'll need to work with your email provider to re-set your password. Find their webpage. You'll need to login, and since you have lost or forgotten your password, look for a "I have forgotten my password" option. It's possible that your browser "knows" the password and just lets you in to the website. If so, you'll have to open the browser's password store to see what is stored there. If your email account is provided by your ISP, and you change your primary email address's password, you may also need to re-set it on your router or modem. Very often the ISP uses the primary email address to authenticate your Internet login.