Sometimes, there are so many things to do that it seems impossible to do any of it. You want to, but everything's just blocked and every day that goes by just adds to the pressure.
It's a bit like having a hundred people trying to squeeze through a narrow doorway at the same time. The more they push, the harder it is for anyone to get through.
In this analogy, the best solution is to form a queue and let people through calmly, one at a time.
The same can work for work; by focusing on just one thing at a time, you can dedicate all your mental energy to the task at hand.To do this effectively, you need to stay with the task even if it's difficult. Don't switch to working on something else just because it's difficult. That way, you can actually solve some of the problems that arise, rather than saving them up for later.