I never attended parenting classes before I had my babies, and I believe you will find that there is support there if you need it. I had plenty of support with my first who was formula fed, the midwife visited several times, and then I was handed over to a very nice health visitor who was visiting regularly for a long time.
In the very early days, I was re-hospitalised as got extremely ill, and I was there without my baby on a surgical ward, off my head on medications and unable to breast feed, and I still got support from a breastfeeding counsellor, because I needed to be shown how to deal with milk coming in etc. She talked to me a bit about bottles too, to put my mind at ease about my son at home with his dad.
In fact I ended up with plenty of support, as I had PND, there was counselling arranged, a group to learn about PND and support others, a place in a baby massage group arranged, a HomeStart referral (I still hear from them now and my children are nine years old and six years old, we still do the Christmas parties and free trips), family support workers from the children's centre (also still friendly with), and that's just what I can recall right now.
There's no lack of support if you ask for it, honestly.
My second was exclusively breast fed (no bottles, whimper, no dummies!) and the only different was that I attended a breast feeding support group as well as all that support.
I am discussing this a lot with my mum, as she is retraining from mental health to health visiting, and she's learning a lot of stuff about babies and development. She calls me all the time to apologise for getting XYZ wrong when we were little, and I tell her it's silly to worry about stuff, she did the best she could with the knowledge she had.
I do think they should discuss making up bottles as a part of parent craft, but even if they don't, I think you'll be well set with all the other support there.