Hi kittens vaccs usually start at 9 weeks then the 2nd jab at 12.
Food - as said before try and keep them on whatever they are currently being fed and gradually introduce new food over time. Any food with a high meat content is good, there are lots & lots of posts in health sections regarding food.
Unless the kitten is feral then it should already be litter trained but its not that difficult to teach.
I would probably feed wet food morning & evening and leave dry down all day especially as they are kittens they will want feeding little & often.
There is lots of good advice on here if you take a look around.
good luck
