Why can’t I use my PayPal to buy something online ? And I have been doing it pls confirm what’s going on

Kindnesswellman wrote:

I need you to help me use my PayPal online to buy things

That sounds like an issue for PayPal, not Apple: Help Center - PayPal

If you're wanting to use PayPal to make purchases from Apple, you need to add it to your Apple account, assuming it's an accepted form of payment in your country or region. See here: Payment methods that you can use with your Apple Account - Apple Support