A question ladies...

I wondered if you can help answer a question please? I apologize if it sounds silly...

I recently attended my first full Zikr which I thoroughly enjoyed, even though I spent most of my time sat at the back out of the way. As many of you know I've been learning about Islam for almost 2 years now and am enjoying it immensely. I felt a bit awkward not joining in the prayers etc and wanted to give it a try, but have no clue how or what to do. How do I learn this? Also, what happens if you have knee injuries and find kneeling extremely painful. Is there a way around this? Its one of the things that worries me the most. Thank you ladies, I appreciate all you help!

Hugs!! X