At this time, it's not possible to change your password and security questions via the PayPal app. You can always change them by going to paypal.com. 

Here's how to change your password:

1. Go to your Settings.
2. Click the Security tab above your name.
3. Click Update next to "Password."
4. Confirm your current password, enter your new password twice, and click Change Password.

Here's how to change your security questions:

1. Go to your Settings.
2. Click the Security tab above your name.
3. Click Update under "Security questions."
4. From the "Security question 1" and "Security question 2" dropdown menus, select a question and type its answer.
5. Click Save.

We recommend you change your password and security questions from time to time.

You may bypass our FAQs steps and update your password and security questions by going  to the Security page directly.