From time to time we are getting enquires to teach adults to swim and/or prepare them for an aircraft exams.

Yes, cabin crew should be able to swim.

Cabin crew do not have to demonstrate extraordinary abilities for swimming, but must be able to swim for up to 50 meters, across a pool about 2 meters deep. As well as climbing out to pool side not using the stairs.

I cannot swim, but I want to be cabin crew.
There is no swimming test during the recruitment phase, but you must learn how to swim before you board on the plane. During the cabin crew licensing training, you must prove that you are not afraid of water and, if needed, you can swim.

So, if you cannot swim at the moment of your recruitment, you have some extra time to take swimming lessons before your employment.