Solids at this age are not
about replacing milk feeds, it is about getting them used to different tastes and textures and that's it. Milk should ALWAYS be offered first until at least 9 months and solids at least 45 minutes after. DS2 would have a bf after his solids for a "drink".
talks about solids and bf babies. The quicker you introduce solids, the more likely you are to end up with a constipated baby. DS2 started at 7 months and he was 10 months before he was on 3 solid meals a day and he was never constipated; we worked to the motto "food is fun until he is 1". You should wait at least 3 days between each introduction of a fruit/veg to check for reactions and 1-2tsps is more than enough in the early days. You can introduce water if you like, however DS2 wouldn't drink heaps of it until he was 12 months and he used to bf for a drink as well as for food.