To keep your food and drinks cold enough the mini fridge should be at a temperature of 40 F degrees.
For keeping foods such as dairy and milk that is also dairy the temperature of the mini fridge really should be around 38 F or below if possible.
But as long as your mini fridge is at a temperature of at least 40 F the mini fridge is working properly and keeping the food and drinks cold.
You can and should use a refrigerator thermometer to make sure that your mini fridge as well as your regular full size refrigerator is keeping cold enough.
If the temperature gets above 40 F in the refrigerators then your food could spoil.
But just for drinks the drinks would just be warm and not cold.