Stroke clinic advice when you've never attended

Hi, I was looking at the stroke clinics. Sadly, the closest one is a bit away. What are we looking for in clinics. I did get the indication from the coach that it can be positive in terms of stroke technique. It is also doing some video watching. The question I have is how much of this do you do? I learned as a middle aged adult to really swim (not just turtling free) so I can see some video watching but I already do that. The comments say all 4 strokes. It doesn't say whether or not there is a limit on the # of people attending. If you have 3 hours, not sure how much time I would get. Can someone give me what happens at the clinics, since they are not near us? Thanks, Vic