Hello @Hi !
Do you mean that you're looking to disconnect PayPal from your store? If so, you would go to the STORE tab in the site editor, click the Settings option on the left, and then click the Checkout option that appears on the left. There you'll see an option to enable to disable PayPal as a payment processor.
If you're referring to something else, please let me know. I'm not exactly sure what you mean by logging out of PayPal through Weebly. You can always go directly to paypal.com and log out of your PayPal account there.
