How to learn to fall asleep if there is constant noise?
You need to learn to achieve complete bodily relaxation and consciously introduce yourself into the borderline state between wakefulness and sleep. In this state, the external noise will not be of fundamental importance. you will fall asleep more and more. Meditation can help you approach this state.
I also cannot sleep with noise. Earplugs are annoying. Valerian tea helps, severe fatigue. Recently the windows were changed, it became easier.
Interestingly, to the sound of my TV, I sleep well and even wake up when my wife makes the sound quieter. But if the sound comes through the wall from neighbors, then in this case it annoys me and I will not be able to fall asleep. In this case, I use bears and fall asleep calmly.