Keeping painful tasks is difficult. So, first of all, you need to release yourself from suffering. To this purpose, you need to recognize the reality that your brain ability limits your understanding speed.
Let’s compare it to a marathon. If you run without knowing the pace at which you can keep running, you go tired and pace down on the way. It is important to know your pace and keep it. Even if you feel the pace is slow, you can run longer by keeping the pace. By running long, your physical strength gradually increases, and your pace goes up.