How to add custom PayPal button and passing on fees to customer?

Is there way to use a custom PayPal button or a way to pass on the fees to our customers? If so please direct to me on how I can add that to my form. 

There's no direct option to embed the button in your form, but you can change Jotform's button image to make it look like PayPal button.

ex.

As for PayPal fees, You could add a product in your PayPal Form and named it PayPal fee. Then set it to required so that it cannot be unchecked.

I hope that helps. Let us know if you have any questions or if you need further assistance.