The short answer is Yes!
Since the the General Data Protection Regulation 2016/679 came into force, your end customers are obliged to accept both your terms and conditions and your data protection declaration when they buy your services and/or products.
Under Account > Company data you can upload your general terms and conditions and your data protection declaration. General terms and conditions, the data protection declaration and your legal notice should be included in your bookingkit account as well as directly on your website. Your integrated bookingkit widget allows your customers view your T&C at any time:
During checkout your customers have to accept your terms and conditions and data protection declaration by ticking respective checkbox. Only then can they make a booking.