In my experience, library book groups are ... bleh. They tend to attract a lot of older retired people, which is all fine, but I prefer a mix of ages in my book groups. Also, most (all I've had experience with) don't let readers choose their own books. The library orders x number of copies of whatever book they decide on. So you don't have much say in what you read.
I'd have a look at the meetup reading groups and if those don't suit you, start your own! I've started two since moving to the UK and both have been really successful!
I'd like to join your on-line group but I already belong to three book groups and don't think I can handle another one!
But best of luck with it all!