I’d like my son to be able to utilize sippy cups for milk/water when he turns 1. I’m wondering what is the best cup for transition?

He is currently 10 months and has been ebf and I’m a stay at home mom so he doesn’t use cups or bottles. (I feed directly from my breast and I don’t pump so I can’t put breastmilk into a bottle for him to practice using/holding). I feel so bad. My friends babies are much younger 7/8 months and are holding their own bottles feeding themselves. I’m not sure mine can since I’m his main food source/hydration. 😕