Predicted grades for internships

Does anyone know what I should do bc I've just applied for two internships at Tesco's and was automatically unsuccessful bc I believe I selected the "no" option when they asked me if I have any predicted grades.

At the moment I've just started second year at my uni and not 1000% sure how to calculate predicted grades. Like should I just calculate the average grades based on what I got in my first year's assignments?

Should I just randomly put a 2:1 or a 1st or something if I wanted to apply for an internship at Tesco's? Bc if I tell them I don't have a predicted grade, Tesco will end up automatically rejecting me and telling me I've been unsuccessful. Someone plz gimme some advice on what to do.