To change your personal information like name, email, picture, or password, you have to go to the Profile Settings.
You can go to Profile Settings, from the bottom section. First, click on the arrow icon. Then, click on "Profile Settings".
Now, click on the profile picture icon, and you will get the option to upload your profile picture.
You can also change your name or your email address from here. To learn more about changing email, please check this article about making email default.