The European Payment Services Directive (PSD2) improves the security of online purchases. For this reason, they must be authorised through CaixaBankNow digital banking (the CaixaBank app or website). This option affects all cards, including any cards you have granted to other beneficiaries (for example, a child).
You will continue to make purchases as you have done in the past, by entering your card details in the e-commerce store. When you have completed this step, you will have to authorise the purchase via CaixaBankNow online banking: you can do this from your phone using the CaixaBankNow application or from your computer via the CaixaBankNow website.