Welcome Tcofran,
As Gloeiwurmpie said, the milk has got to go, unfortunately as long as you keep offering milk, your little one will wake up for it.
at around 13 months, we realized my daughter was just using the breastfeeding as a soother to get back to sleep rather than needing the milk, so we quite- cold turkey , yes there were 2-3 nights of fighting, because she wanted the milk, but your son is also much older now, so you could also probably explain to him which might make it easier.
I know my Paed said they should really be off all bottles by 2, think it may have even been a bit sooner (milk through a bottle teat is also bad for their teeth- and then just have full cream milk in a sippy cup in the day no night time milk ( as GW said they dont really need it for nutritional reasons past 6 months)
Maybe just explain to your son he is a big boy now and doesn't need a bottle at night, but if he wakes up you will go comfort him or give him water etc, if he has a temper tantrum, just ride it out, we did with my daughter, we sat with her while she had a bit of a cry and offered cuddles and water instead and after a few nights, she was already sleeping so much better. I know a lot of parents who tell their kids they giving the bottles to the bottle fairy and leave them out one night and then next day the child gets a present from the bottle fairy and the bottles are gone.
In terms of the talking, if you are concerned then I would suggest chatting to your Dr, my Paed said that its easier to fix any speech problems when they younger, than leaving it, perhaps he is just taking a bit longer because he is a boy, but your Dr will be able to give you some advice there.
Good luck, let us know how it goes