How can I reset Google play store pin if I can't remember it? I want to download apps that my parental controls won't let me do and I can't remember my pin. How can I change it please or reset it?
The easiest way out is to reset your Google account by;

Change or reset your password

You can change your password for security reasons or reset it if you forget it. Your Google Account password is used to access many Google products, like Play-store, Gmail and YouTube.

Change your password


  
  Sign in to My Account.
  Under "Sign-in &amp; security," select Signing in to Google.
  Choose Password. If you see a prompt to sign in again, sign in. 
  Enter your new password, then select Change Password.
  


Reset your password


  *Go to the Account support page.
  *Follow the instructions. You'll be asked some questions to confirm it's your account and an email will be sent to you. If you don’t get an email:
  
  
  Check your Spam or Bulk Mail folders
  Add noreply@google.com to your address book.
  Request another email.
  Check all email addresses you might've used to sign up or sign in to your account.
  
  
  *Choose a password that you haven't already used with this account. Learn how to create a strong password.


Source: Google Account Help