Changeing your age is simple, you go to edit profile settings. You should see a tab that says "Preferences". You click that and it should show your gender, Firstname, and level.
To change your brainly profile you should see in edit profile settings a tab that says "Password". There are two ways to change your password, you could send a notification to your email which will guide you through how to change your profile or you type in your old password but since you forgot it I would go with option A.
Explanation:
Just so you wont forget it again, I reccomend writing it down or saving the password to your computer.
Limb is akin to a branch. A branch is a part of a whole treed. A stanza is a part of an entire poem. Therefore, a limb is the equivalent of a branch which is the equivalent of a stanza to a poem.