Hey!
I totally understand how you feel - whilst I've never been to an industry-specific event, I felt a similar way (and often still do!) before most networking events at firms so I can share what has helped me! People don't expect you to know everything - they just appreciate genuine interest in the area.
The easiest way to handle conversations is to focus on their experience, not on applications. I would start with something simple such as "
I'm a student interested in this field, and I was wondering if you'd be happy to share what the work actually looks like day to day". This way, you give them some context on your background but it allows them to tell you about their career as well.
One of the key things to remember about networking events (both generally and industry-specific) is that the majority of people at them will genuinely enjoy their career, and will be more than happy to chat to you about it! Some starting points for conversations could be:
1. Ask what's changing in the industry and how it affects their clients
2. Ask what parts of the work they find most interesting or surprising
3. Ask how different teams work together on matters in that sector
4. Ask what they wish they'd known earlier about the practice area
These questions feel natural, don't put anyone on the spot, and give you a really good sense of the firm's culture and the type of work they do. Above all, have a think about what genuinely interests you about the industry and what you'd like to know more about - frame your questions around those things!
I would also try not to stress about being awkward (easier said than done, I know!). At these events, people are used to explaining what they do and they go to these events to talk to people who are interested in the area too - a bit of curiosity can go a long way!
I hope that helps, and best of luck with the event - I'm sure it'll go great!