Battlefield 6 is taking a unique approach to its weapon unlock system compared to what you might expect from its predecessors, mixing in both standard rank requirements and customized challenges for each class. Rather than being able to simply grind long enough to unlock everything Battlefield 6 has to offer, you'll need to adjust your playstyle and experiment with aspects of each class you might not have considered using before.
While some of these class challenges can be a bit more time-consuming and a little convoluted in how to unlock them in the first place, the rewards are more than worth the effort. Each Class Assignment is visible right from the start, but you'll first need to achieve Rank 20 and complete every prerequisite Assignment, as it won't save any progress until that