Pagey, it's AA I've been to, not NA, but same difference. You won't be expected to speak as such, no. Most groups I attended were happy for newbies, people from other groups just passing through, or those having an off day to just sit back a little maybe just outside the circle and not say a single word the whole session if that's how they felt. By the same token if you feel you wanna introduce yourself to the group that's fine too, and there'll almost certainly be opportunity for you to do that at some point. Might be a quick go round the room at the start of the meeting with the regular members giving a quick summary of what's been happening to them that week, or it might flow more naturally as part of the discussion on whatever the topic is that night with people sharing their own related experiences.
Different local groups will have their own preferred way of doing things at a meeting according to that group's 'conscience' so bear that in mind if after a visit or two you start to feel NA might not be for you. It might just be that particular group that doesn't suit you, another one might. The local groups around you can be different enough to make trying as many of them as you can the first few weeks worthwhile, but there's general similarities. Again, I'm more talking AA here but ethos, group structure and format apply equally to NA: Of the four groups I tried some were more like reading groups that spent a coupla hours reading through a chapter from The Big Book, sharing whichever of their experiences seemed best to illustrate the text, others were a bit more general discussion but again typically the group leader that night or an invited speaker from another group maybe or from up the AA local / regional hierarchy for instance would kick off with a talk around a particular topic like their experience and understanding of walking some of the 12-Steps that they've done or whatever that others can then share on afterwards. Always lots of war stories about how drink and drugs laid someone low till they saw the light, which can occasionally be quite funny or interesting, but is mostly just really, really boring to listen to.
one thing that kinda phased me was that it's not the done thing entering into anything like a proper conversation with the person who's just shared. People can get up and say something about how things are and have been lately for them, how much they're struggling and what with, addiction-wise or real world practical stuff, so long as it's kinda relevant and on-topic, and someone can come in after them and use their own experiences to expand on the theme, but noone ever picks up on anything to go back to a speaker directly, either with advice or with questions to draw out more info that could be bigger picture / fresh perspective useful for someone. It's actively discouraged quite often, replying directly back to someone, and sometimes referred to pejoratively as 'cross-talk'. Seems to be almost like one-on-one conversation is deemed to be undermining the group ethos. I just found it kind of odd. That said you've obviously get lots of conversation going among individuals before and after the group session proper where more personal and / or private issues can be raised, not to mention the support networks that exist like that between sponsors and newer members that I think is intended for your more in depth investigation of core principles without intruding on the group's time as a whole. I met a few seriously decent people who I could genuinely relate to who right from off at my first meeting made a point of introducing themselves to the new guy making sure I was made to feel welcome and looked after, being just as quick with the offer of a friendly ear and good advice in later weeks if ever I asked it of them. I think probably it's the networks of support you develop with people like that as a long-term member that's the key thing to NA / AA, much more so than than the dogma. You'll work out pretty quickly which of the regulars have got their shit together and which of them you relate to best depending where you're at.