I also have the same issue with my 7 month old baby.I did not give water until she turn 6 months.When I start giving water,she always gag on it.She seems like doesn't like to drink water.I use richell training cup to train her but I feel that at times she will get choke on water and reject drinking water.
After that I use evorie silicone straw sippy bottle,slowly she begin to like drinking water.
Not sure if u want to try coz what works for my baby may not work best on other babies.
But I understand how u feel because I'm so worried that next time she doesn't want or like to drink water :( But I'm glad now she likes to drink water using the evorie.
Keep offering if baby really refused then don't force too hard.