I could just leave this post there.
But seriously, you probably won't be good at something the first time you do it. So why would you expect yourself to be? One thing I notice when I'm training is that people expect that they are going to be a kettlebell swing/wall ball/burpee/plank/whatever random exercise we ask you to do expert the first time they try it. This is not reasonable. EXERCISES ARE ARBITRARY AND MADE UP. There's no reason you should know how to do them.
One of the things I love about fitness is that it is a low stakes way to be a beginner. What I mean by that is, when we become adults, we often fall into doing only the things we are good at. And that's okay--the reason we do them and are good at them is often because we enjoy them. But learning and experiencing the new is one of the amazing parts of being human. But we shy from it because trying new things can be incredibly stressful, for example, at work, when failure has real consequences. However, not being a kettlebell master on day one has very low stakes. If it is ugly and messy (but safe), who cares? If you try an exercise and it's uncoordinated, who cares? Your training is just training. It should be about learning.
Release yourself from that unhelpful idea. When you walk into a session and we ask you to do something you've never done before (or you've only done a few times) let yourself be a beginner. Let yourself be bad at it. Give yourself credit for being brave enough to take a risk. Because that's a way more important and useful skill than a kettlebell swing.