How can i add paypal to my wallet

See the following Apple articles:

Payment methods you can use with your Apple ID

Payment methods you can use with your Apple ID – Apple Support (UK)

Change, add or remove Apple ID payment methods

Change, add or remove Apple ID payment methods – Apple Support (UK)

You can’t use PayPal directly in the wallet, but you can get a PayPal credit or debit card and put that in the Wallet.