How to train my 9 months old to drink from a cup? Or is it too early to train ?

I used the pigeon training straw and have seen baby used it successfully but noticed really depend on baby mood because sometimes will just bite the straw. Not yet transitioned to the normal straw because seems like need force to suck. For small amount i try feeding from an open cup after solids. Small wins - at least a little bit of water goes in while a lot probably ends up everywhere else.