Hi there,
According to my analysis & understanding, you have a Magento website that is using Porto theme and you want to make few customizations/fixes in your site. Can you please provide your site urls for better understating of the issues? Do you want to add the option to select and delete products from minicart or you want to have a button that will empty the whole cart?
Look forward to hearing from you & start further discussion thru' private chat.
Regards,
YK
LEADconcept