When it comes to learning faster it also depends on the subject. Some people are good at learning logical subjects while other find it easy to learn theory. Aptitude and interest is also a contributor. Then there are some who are always interested in learning. The point is that it comes after practice. Whatever your type is, if you practice then you will start learning faster.
When you are learning decide the time before hand. So in that limited time of 45–50 mins focus on learning and understanding. Then take a 15 min gap and do something relaxing. Then again learn for 45 mins. But this time you will learn something else. Fox example if you studied maths then took a gap. After the gap do not go for maths or physics. Go for something altogether different. This gives you logical part of brain extra time to process the information.
Revision is necessary because when you are revising you are creating new memory.
Also don’t learn in a boring way. When you learned to ride a bike, you were enthusiastic. Similarly bring that excitement in learning.
Use memory techniques to remember clearly. You can use chain method, Mnemonics and even memory palace depending on the requirement.
So what does a memory technique do?
It makes the memory interesting by associating it with some image. As it is interesting you will remember it.